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Paleomagnetism
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This term is also sometimes used for natural remanent magnetization.
Magnetic stripes are the result of reversals of the Earth's field and seafloor spreading. New oceanic crust is magnetized as it forms and then it moves away from the ridge in both directions. The models show a ridge (a) about 5 million years ago (b) about 2 to 3 million years ago and (c) in the present.[1]
Paleomagnetism (or palaeomagnetism in the United Kingdom) is the study of the record of the Earth's magnetic field in rocks, sediment, or archeological materials. Certain minerals in rocks lock-in a record of the direction and intensity of the magnetic field when they form. This record provides information on the past behavior of Earth's magnetic field and the past location of tectonic plates. The record of geomagnetic reversals preserved in volcanic and sedimentary rock sequences (magnetostratigraphy) provides a time-scale that is used as a geochronologic tool. Geophysicists who specialize in paleomagnetism are called paleomagnetists.
Paleomagnetists led the revival of the continental drift hypothesis and its transformation into plate tectonics. Apparent polar wander paths provided the first clear geophysical evidence for continental drift, while marine magnetic anomalies did the same for seafloor spreading. Paleomagnetism continues to extend the history of plate tectonics back in time and are applied to the movement of continental fragments, or terranes.
Paleomagnetism relied heavily on new developments in rock magnetism, which in turn has provided the foundation for new applications of magnetism. These include biomagnetism, magnetic fabrics (used as strain indicators in rocks and soils), and environmental magnetism.
Contents
[hide]
1 History
2 Fields of paleomagnetism
3 Principles of remanent magnetization
3.1 Thermoremanent magnetization
3.2 Detrital remanent magnetization
3.3 Chemical remanent magnetization
3.4 Isothermal remanent magnetization
3.5 Viscous remanent magnetization
4 Paleomagnetic procedure
4.1 Collecting samples on land
5 Applications
6 See also
7 Notes and references
8 Further reading
9 External links
History[edit]
Main article: History of geomagnetism
As early as the 18th century, it was noticed that compass needles deviated near strongly magnetized outcrops. In 1797, Von Humboldt attributed this magnetization to lightning strikes (and lightning strikes do often magnetize surface rocks).[2][3] In the 19th century studies of the direction of magnetization in rocks showed that some recent lavas were magnetized parallel to the Earth's magnetic field. Early in the 20th century, work by David, Brunhes and Mercanton showed that many rocks were magnetized antiparallel to the field. Japanese geophysicist Motonori Matuyama showed that the Earth's magnetic field reversed in the mid-Quaternary, a reversal now known as the Brunhes-Matuyama reversal.[2]
The British physicist P.M.S. Blackett provided a major impetus to paleomagnetism by inventing a sensitive astatic magnetometer in 1956. His intent was to test his theory that the geomagnetic field was related to the Earth's rotation, a theory that he ultimately rejected; but the astatic magnetometer became the basic tool of paleomagnetism and led to a revival of the theory of continental drift. Alfred Wegener first proposed in 1915 that continents had once been joined together and had since moved apart.[4] Although he produced an abundance of circumstantial evidence, his theory met with little acceptance for two reasons: (1) no mechanism for continental drift was known, and (2) there was no way to reconstruct the movements of the continents over time. Keith Runcorn[5] and Edward A. Irving[6] constructed apparent polar wander paths for Europe and North America. These curves diverged, but could be reconciled if it was assumed that the continents had been in contact up to 200 million years ago. This provided the first clear geophysical evidence for continental drift. Then in 1963, Morley, Vine and Matthews showed that marine magnetic anomalies provided evidence for seafloor spreading.
Fields of paleomagnetism[edit]
Paleomagnetism is studied on a number of scales:
Secular variation studies look at small-scale changes in the direction and intensity of the Earth's magnetic field. The magnetic north pole is constantly shifting relative to the axis of rotation of the Earth. Magnetism is a vector and so magnetic field variation is made up of palaeodirectional measurements of magnetic declination and magnetic inclination and palaeointensity measurements.
Earth's magnetic polarity reversals in last 5 million years. Dark regions represent normal polarity (same as present field); light regions represent reversed polarity.
Magnetostratigraphy uses the polarity reversal history of the Earth's magnetic field recorded in rocks to determine the age of those rocks. Reversals have occurred at irregular intervals throughout Earth history. The age and pattern of these reversals is known from the study of sea floor spreading zones and the dating of volcanic rocks.
Principles of remanent magnetization[edit]
The study of paleomagnetism is possible because iron-bearing minerals such as magnetite may record past directions of the Earth's magnetic field. Magnetic signatures in rocks can be recorded by several different mechanisms.
Thermoremanent magnetization[edit]
Main article: Thermoremanent magnetization
Iron-titanium oxide minerals in basalt and other igneous rocks may preserve the direction of the Earth's magnetic field when the rocks cool through the Curie temperatures of those minerals. The Curie temperature of magnetite, a spinel-group iron oxide, is about 580°C, whereas most basalt and gabbro are completely crystallized at temperatures below 900°C. Hence, the mineral grains are not rotated physically to align with the Earth's field, but rather they may record the orientation of that field. The record so preserved is called a thermoremanent magnetization (TRM). Because complex oxidation reactions may occur as igneous rocks cool after crystallization, the orientations of the Earth's magnetic field are not always accurately recorded, nor is the record necessarily maintained. Nonetheless, the record has been preserved well enough in basalts of the ocean crust to have been critical in the development of theories of sea floor spreading related to plate tectonics. TRM can also be recorded in pottery kilns, hearths, and burned adobe buildings. The discipline based on the study of thermoremanent magnetisation in archaeological materials is called archaeomagnetic dating.[7]
Detrital remanent magnetization[edit]
In a completely different process, magnetic grains in sediments may align with the magnetic field during or soon after deposition; this is known as detrital remanent magnetization (DRM). If the magnetization is acquired as the grains are deposited, the result is a depositional detrital remanent magnetization (dDRM); if it is acquired soon after deposition, it is a post-depositional detrital remanent magnetization (pDRM).[8]
Chemical remanent magnetization[edit]
See also: Chemical remanent magnetization
In a third process, magnetic grains grow during chemical reactions, and record the direction of the magnetic field at the time of their formation. The field is said to be recorded by chemical remanent magnetization (CRM). A common form of chemical remanent magnetization is held by the mineral hematite, another iron oxide. Hematite forms through chemical oxidation reactions of other minerals in the rock including magnetite. Redbeds, clastic sedimentary rocks (such as sandstones) are red because of hematite that formed during sedimentary diagenesis. The CRM signatures in redbeds can be quite useful and they are common targets in magnetostratigraphy studies.[9]
Isothermal remanent magnetization[edit]
See also: Remanence
Remanence that is acquired at a fixed temperature is called isothermal remanent magnetization (IRM). Remanence of this sort is not useful for paleomagnetism, but it can be acquired as a result of lightning strikes. Lightning-induced remanent magnetization can be distinguished by its high intensity and rapid variation in direction over scales of centimeters.[10][9]
IRM is often induced in drill cores by the magnetic field of the steel core barrel. This contaminant is generally parallel to the barrel, and most of it can be removed by heating up to about 400 ℃ or demagnetizing in a small alternating field.
In the laboratory, IRM is induced by applying fields of various strengths and is used for many purposes in rock magnetism.
Viscous remanent magnetization[edit]
Main article: Viscous remanent magnetization
Viscous remanent magnetization is remanence that is acquired by ferromagnetic materials by sitting in a magnetic field for some time.
Paleomagnetic procedure[edit]
Collecting samples on land[edit]
The oldest rocks on the ocean floor are 200 mya – very young when compared with the oldest continental rocks, which date from 3.8 billion years ago. In order to collect paleomagnetic data dating beyond 200 mya, scientists turn to magnetite-bearing samples on land to reconstruct the Earth's ancient field orientation.
Paleomagnetists, like many geologists, gravitate towards outcrops because layers of rock are exposed. Road cuts are a convenient man-made source of outcrops.
"And everywhere, in profusion along this half mile of [roadcut], there are small, neatly cored holes ... appears to be a Hilton for wrens and purple martins."[11]
There are two main goals of sampling:
Retrieve samples with accurate orientations, and
Reduce statistical uncertainty.
One way to achieve the first goal is to use a rock coring drill that has a pipe tipped with diamond bits. The drill cuts a cylindrical space around some rock. This can be messy – the drill must be cooled with water, and the result is mud spewing out of the hole. Into this space is inserted another pipe with compass and inclinometer attached. These provide the orientations. Before this device is removed, a mark is scratched on the sample. After the sample is broken off, the mark can be augmented for clarity.[12]
Applications[edit]
Paleomagnetic evidence, both reversals and polar wandering data, was instrumental in verifying the theories of continental drift and plate tectonics in the 1960s and 1970s. Some applications of paleomagnetic evidence to reconstruct histories of terranes have continued to arouse controversies. Paleomagnetic evidence is also used in constraining possible ages for rocks and processes and in reconstructions of the deformational histories of parts of the crust.[3]
Reversal magnetostratigraphy is often used to estimate the age of sites bearing fossils and hominin remains.[13] Conversely, for a fossil of known age, the paleomagnetic data can fix the latitude at which the fossil was laid down. Such a paleolatitude provides information about the geological environment at the time of deposition.
Paleomagnetic studies are combined with geochronological methods to determine absolute ages for rocks in which the magnetic record is preserved. For igneous rocks such as basalt, commonly used methods include potassium–argon and argon–argon geochronology.
Scientists in New Zealand have found that they are able to figure out the Earth's past magnetic field changes by studying 700- to 800-year-old steam ovens, or hangi, used by the Maori for cooking food.[14]
See also[edit]
Book: Geomagnetism
Geophysics
Magnetochemistry
Paleoclimate
Plate reconstruction
Rock magnetism
Notes and references[edit]
Jump up ^ W. Jacquelyne, Kious; Robert I., Tilling (2001). "Developing the theory". This dynamic earth: the story of plate tectonics (online edition version 1.20). Washington, D.C.: U.S. Geological Survey. ISBN 0-16-048220-8. Retrieved 6 November 2016.
^ Jump up to: a b Glen 1982
^ Jump up to: a b McElhinny 2000
Jump up ^ Glen, William (1982). The Road to Jaramillo: Critical Years of the Revolution in Earth Science. Stanford University Press. pp. 4–5. ISBN 0-8047-1119-4.
Jump up ^ Runcorn, S. K. (1956). "Paleomagnetic comparisons between Europe and North America". Proc. Geol. Assoc. Canada. 8: 77–85.
Jump up ^ Irving, E. (1956). "Paleomagnetic and palaeoclimatological aspects of polar wandering". Geofis. Pura. Appl. 33 (1): 23–41. Bibcode:1956GeoPA..33...23I. doi:10.1007/BF02629944.
Jump up ^ Herries, A. I. R.; Adams, J. W.; Kuykendall, K. L.; Shaw, J. (2006). "Speleology and magnetobiostratigraphic chronology of the GD 2 locality of the Gondolin hominin-bearing paleocave deposits, North West Province, South Africa". Journal of Human Evolution. 51 (6): 617–31. doi:10.1016/j.jhevol.2006.07.007. PMID 16949648.
Jump up ^ "Detrital Remanent Magnetization (DRM)". MagWiki: A Magnetic Wiki for Earth Scientists. Retrieved 11 November 2011.
^ Jump up to: a b Tauxe, Lisa (May 24, 2016). "Chemical remanent magnetization". Essentials of Paleomagnetism: Web Edition 3.0. Retrieved 18 September 2017.
Jump up ^ Dunlop & Özdemir 1997
Jump up ^ McPhee & 1988, pp. 21–22
Jump up ^ Tauxe 1998
Jump up ^ Herries, A. I. R.; Kovacheva, M.; Kostadinova, M.; Shaw, J. (2007). "Archaeo-directional and -intensity data from burnt structures at the Thracian site of Halka Bunar (Bulgaria): The effect of magnetic mineralogy, temperature and atmosphere of heating in antiquity". Physics of the Earth and Planetary Interiors. 162 (3–4): 199–216. Bibcode:2007PEPI..162..199H. doi:10.1016/j.pepi.2007.04.006.
Jump up ^ Amos, Jonathan (7 December 2012). "Maori stones hold magnetic clues". BBC News. Retrieved 2012-12-07.
Further reading[edit]
The Wikibook Historical Geology has a page on the topic of: Paleomagnetic dating
Butler, Robert F. (1992). Paleomagnetism: Magnetic Domains to Geologic Terranes. Blackwell. ISBN 0-86542-070-X. Archived from the original on 1999-02-18.
Dunlop, David J.; Özdemir, Özden (1997). Rock Magnetism: Fundamentals and Frontiers. Cambridge Univ. Press. ISBN 0-521-32514-5.
Glen, William (1982). The Road to Jaramillo: Critical Years of the Revolution in Earth Science. Stanford University Press. ISBN 0-8047-1119-4.
McElhinny, Michael W.; McFadden, Phillip L. (2000). Paleomagnetism: Continents and Oceans. Academic Press. ISBN 0-12-483355-1.
McPhee, John (1998). Annals of the Former World. Farrar, Straus and Giroux. ISBN 0-374-10520-0.
Tauxe, Lisa (2010). Essentials of Paleomagnetism. University of California Press. ISBN 0-520-26031-7.
Tauxe, Lisa (1998). Paleomagnetic Principles and Practice. Kluwer. ISBN 0-7923-5258-0.
External links[edit]
Geomagnetism & Paleomagnetism background material
Paleomagnetic Data from NGDC / WDC Boulder
The Great Magnet, The Earth
Paleomagnetic database at the Scripps Institution of Oceanography (MagIC)
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ATX
From Wikipedia, the free encyclopedia
Jump to: navigation, search
This article is about the computer form factor. For other uses, see ATX (disambiguation).
An ATX motherboard
Computer form factors
Listed by PCB size (mm)
WTX (356×425)
AT (350×305)
Baby-AT (330×216)
BTX (325×267)
ATX (305×244)
SSI CEB (305x267)
EATX (Extended) (305×330)
LPX (330×229)
microBTX (264×267)
NLX (254×228)
Ultra ATX (367×244)
microATX (244×244)
DTX (203×244)
FlexATX (229×191)
Mini-DTX (203×170)
EBX (203×146)
Mini-ITX (170×170)
EPIC (Express) (165×115)
Mini ATX (150×150)
ESM (149×71)
Mini-STX (140×147)
Nano-ITX (120×120)
COM Express (125×95)
ESMexpress (125×95)
ETX (114×95)
XTX (114×95)
NUC (102×102)
Pico-ITX (100×72)
PC/104 (-Plus) (96×90)
ESMini (95×55)
SMARC (82×80)
Qseven (70×70)
mobile-ITX (60×60)
CoreExpress (58×65)
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Comparison of some common motherboard form factors
ATX (Advanced Technology eXtended) is a motherboard configuration specification developed by Intel in 1995 to improve on previous de facto standards like the AT design. It was the first major change in desktop computer enclosure, motherboard and power supply design in many years, improving standardization and interchangeability of parts. The specification defines the key mechanical dimensions, mounting point, I/O panel, power and connector interfaces between a computer case, a motherboard and a power supply.
ATX is the most common motherboard design.[1] Other standards for smaller boards (including microATX, FlexATX, nano-ITX, and mini-ITX) usually keep the basic rear layout but reduce the size of the board and the number of expansion slots. Dimensions of a full-size ATX board are 12 × 9.6 in (305 × 244 mm), which allows many ATX chassis to also accept microATX boards. The official ATX specifications were released by Intel in 1995 and have been revised numerous times since. The most recent ATX motherboard specification is version 2.2.[2] The most recent ATX12V power supply unit specification is 2.31,[3] released in February 2008. EATX (Extended ATX) is a bigger version of the ATX motherboard with 12 x 13 inch dimensions. Advantages of having an EATX motherboard is the support for dual Xeon CPUs.
In 2004, Intel announced the BTX (Balanced Technology eXtended) standard, intended as a replacement for ATX. As of 2018[update], the ATX design still remains popular, while BTX has been introduced by some manufacturers.
Contents
[hide]
1 Connectors
2 Variants
3 Power supply
3.1 Physical characteristics
3.2 Main changes from AT and LPX designs
3.2.1 Power switch
3.2.2 Power connection to the motherboard
3.2.3 Airflow
3.3 ATX power supply revisions
3.3.1 Original ATX
3.3.2 ATX12V 1.x
3.3.2.1 ATX12V 1.0
3.3.2.2 ATX12V 1.1
3.3.2.3 ATX12V 1.2
3.3.2.4 ATX12V 1.3
3.3.3 ATX12V 2.x
3.3.3.1 ATX12V 2.0
3.3.3.2 ATX12V v2.01
3.3.3.3 ATX12V v2.1
3.3.3.4 ATX12V v2.2
3.3.3.5 ATX12V v2.3
3.3.3.6 ATX12V v2.31
3.3.3.7 ATX12V v2.32
3.3.3.8 ATX12V v2.4
3.4 ATX power supply derivatives
3.4.1 SFX
3.4.2 TFX
3.4.3 WTX
3.4.4 AMD GES
3.4.5 EPS12V
3.5 Recent specification changes and additions
3.6 Interchanging PSUs
3.7 Efficiency
4 See also
5 References
6 External links
Connectors[edit]
ATX I/O plates for motherboard rear connectors
On the back of the computer case, some major changes were made to the AT standard. Originally AT style cases had only a keyboard connector and expansion slots for add-on card backplates. Any other onboard interfaces (such as serial and parallel ports) had to be connected via flying leads to connectors which were mounted either on spaces provided by the case or brackets placed in unused expansion slot positions.
ATX allowed each motherboard manufacturer to put these ports in a rectangular area on the back of the system with an arrangement they could define themselves, though a number of general patterns depending on what ports the motherboard offers have been followed by most manufacturers. Cases are usually fitted with a snap-out panel, also known as an I/O plate or I/O shield, in one of the common arrangements. If necessary, I/O plates can be replaced to suit a motherboard that is being fitted; the I/O plates are usually included with motherboards not designed for a particular computer. The computer will operate correctly without a plate fitted, although there will be open gaps in the case and the EMI/RFI screening will be compromised. Panels were made that allowed fitting an AT motherboard in an ATX case. Some ATX motherboards come with an integrated I/O plate.
ATX also made the PS/2-style mini-DIN keyboard and mouse connectors ubiquitous. AT systems used a 5-pin DIN connector for the keyboard and were generally used with serial port mice (although PS/2 mouse ports were also found on some systems). Many modern motherboards are phasing out the PS/2-style keyboard and mouse connectors in favor of the more modern Universal Serial Bus. Other legacy connectors that are slowly being phased out of modern ATX motherboards include 25-pin parallel ports and 9-pin RS-232 serial ports. In their place are onboard peripheral ports such as Ethernet, FireWire, eSATA, audio ports (both analog and S/PDIF), video (analog D-sub, DVI, HDMI, or DisplayPort), extra USB ports, and Wi-Fi.
Variants[edit]
ATX, Mini-ITX, and AT motherboard compatible dimensions and bore positions
ATX motherboard size comparison; rear is on left.
FlexATX (229 × 191 mm)
microATX (244 × 244 mm)
Mini ATX (284 × 208 mm)
Standard ATX (305 × 244 mm)
Extended ATX (EATX) (305 × 330 mm)
WTX (356 × 425 mm)
Several ATX-derived designs have been specified that use the same power supply, mountings and basic back panel arrangement, but set different standards for the size of the board and number of expansion slots. Standard ATX provides seven slots at 0.8 in (20 mm) spacing; the popular Micro-ATX size removes 2.4 inches (61 mm) and three slots, leaving four. Here width refers to the distance along the external connector edge, while depth is from front to rear. Note each larger size inherits all previous (smaller) colors area.
Note: AOpen has conflated the term Mini ATX with a more recent 15 × 15 cm (5.9 × 5.9 in) design. Since references to Mini ATX have been removed from ATX specifications since the adoption of microATX, the AOpen definition is the more contemporary term and the one listed above is apparently only of historical significance.
A number of manufacturers have added one, two or three additional expansion slots (at the standard 0.8 inch spacing) to the standard 12-inch ATX motherboard width.
Form factors considered obsolete in 1999 included Baby-AT, full size AT, and the semi-proprietary LPX for low-profile cases. Proprietary motherboard designs such as those by Compaq, Packard-Bell, Hewlett Packard and others existed, and were not interchangeable with multi-manufacturer boards and cases. Portable and notebook computers had custom motherboards unique to their particular products.[4]
Name
Organization
Year
Dimensions
Slots
Remarks
ATX Intel 1995 12 × 9.6 in (305 × 244 mm) 7 Original, successor to AT motherboard
SSI CEB Server System Infrastructure Forum 12 × 10.5 in (305 × 267 mm) Compact Electronics Bay
SSI MEB Server System Infrastructure Forum 2011 16.2 × 13 in (411 × 330 mm) Midrange Electronics Bay
SSI EEB Server System Infrastructure Forum 12 × 13 in (305 × 330 mm) Enterprise Electronics Bay
SSI TEB Server System Infrastructure Forum 12 × 10.5 in (305 × 267 mm) Thin Electronics Bay, for rack-mount, has board component height specification
micro ATX Intel 1997 9.6 × 9.6 in (244 × 244 mm) 4 Can fit in to ATX, and EATX cases.
FlexATX Intel 1997 9 × 7.5 in (229 × 191 mm) 3
Extended ATX (standard) Supermicro/Asus 12 × 13 in (305 × 330 mm) 7 Screw holes not completely compatible with some ATX cases. Designed for dual CPUs, and quad double slot video cards.wi
Extended ATX (commonly) 12 × 10.1 in (305 × 257 mm), 12 × 10.4 in (305 × 264 mm), 12 × 10.5 in (305 × 267 mm) and 12 × 10.7 in (305 × 272 mm) 7 Screw holes not completely compatible with EEB
EE-ATX Supermicro 13.68 × 13 in (347 × 330 mm) Enhanced Extended ATX
Ultra ATX Foxconn 2008 14.4 × 9.6 in (366 × 244 mm) 10 Intended for multiple double-slot video cards, and dual CPUs,
XL-ATX EVGA 2009 13.5 × 10.3 in (343 × 262 mm)
XL-ATX Gigabyte Corporation 2010 7
XL-ATX Micro-Star International 2010 13.6 × 10.4 in (345 × 264 mm) 7
WTX Intel 1998 14 × 16.75 in (356 × 425 mm). Discontinued 2008
Mini-ITX Via Technologies 2001 6.7 x 6.7in (170 × 170 mm). 1 Aimed at home theatre or other fanless applications
BTX Intel 2004 12.8 × 10.5 in (325 × 267 mm) 2 Canceled 2006. Also micro, nano, and pico variants. Not generally compatible with ATX mounting.
HPTX EVGA Corporation 2010 13.6 × 15 in (345 × 381 mm) 7 Dual processors, 12 RAM slots
SWTX Supermicro 2006 16.48 × 13 in (419 × 330 mm) and others 4 Quad processors, not compatible with ATX mounting
Although true E-ATX is 12 × 13 in (305 × 330 mm) most motherboard manufacturers also refer to motherboards with measurements 12 × 10.1 in (305 × 257 mm), 12 × 10.4 in (305 × 264 mm), 12 × 10.5 in (305 × 267 mm) and 12 × 10.7 in (305 × 272 mm) as E-ATX. While E-ATX and SSI EEB (Server System Infrastructure (SSI) Forum's Enterprise Electronics Bay (EEB)) share the same dimensions, the screw holes of the two standards do not all align; rendering them incompatible.
In 2008, Foxconn unveiled a Foxconn F1 motherboard prototype, which has the same width as a standard ATX motherboard, but an extended 14.4" length to accommodate 10 slots.[5] The firm called the new 14.4 × 9.6 in (366 × 244 mm) design of this motherboard "Ultra ATX"[6] in its CES 2008 showing. Also unveiled during the January 2008 CES was the Lian Li Armorsuit PC-P80 case with 10 slots designed for the motherboard.[7]
The name "XL-ATX" has been used by at least three companies in different ways.
In September 2009, EVGA Corporation had already released a 13.5 × 10.3 in (343 × 262 mm) "XL-ATX" motherboard as its EVGA X58 Classified 4-Way SLI.[8]
Gigabyte Technology launched another XL-ATX motherboard, with model number GA-X58A-UD9 in 2010 measuring at 13.6 × 10.3 in (345 × 262 mm), and GA-X79-UD7 in 2011 measuring at 12.8 × 10.0 in (324 × 253 mm). In April 2010, Gigabyte announced its 12.8 × 9.6 in (325 × 244 mm) GA-890FXA-UD7 motherboard that allowed all seven slots to be moved downward by one slot position. The added length could have allowed placement of up to eight expansion slots, but the top slot position is vacant on this particular model.
MSI released MSI X58 Big Bang in 2010, MSI P67 Big Bang Marshal in 2011, MSI X79 Xpower Big Bang 2 in 2012 and MSI Z87 Xpower in 2013 all of them are 13.6 × 10.4 in (345 × 264 mm). Although these boards have room for additional expansion slots (9 and 8 total, respectively), all three provide only seven expansion connectors; the topmost positions are left vacant to provide more room for the CPU, chipset and associated cooling.
In 2010, EVGA Corporation released a new motherboard, the "Super Record 2", or SR-2, whose size surpasses that of the "EVGA X58 Classified 4-Way SLI". The new board is designed to accommodate two Dual QPI LGA1366 socket CPUs (e.g. Intel Xeon), similar to that of the Intel Skulltrail motherboard that could accommodate two Intel Core 2 Quad processors and has a total of seven PCI-E slots and 12 DDR3 RAM slots. The new design is dubbed "HPTX" and is 13.6 × 15 in (345 × 381 mm).[9]
Power supply[edit]
See also: Power supply unit (computer)
The ATX specification requires the power supply to produce three main outputs, +3.3 V, +5 V and +12 V. Low-power −12 V and +5 VSB (standby) supplies are also required. The −12 V supply was primarily used to provide the negative supply voltage for RS-232 ports and is also used by one pin on conventional PCI slots primarily to provide a reference voltage for some models of sound cards. The 5 VSB supply is used to produce trickle power to provide the soft-power feature of ATX when a PC is turned off, as well as powering the real-time clock to conserve the charge of the CMOS battery. A −5 V output was originally required because it was supplied on the ISA bus; it was removed in later versions of the ATX standard, as it became obsolete with the removal of the ISA bus expansion slots (the ISA bus itself is still found in any computer which is compatible with the old IBM PC specification (e.g., not found in the PlayStation 4.[10])
Originally, the motherboard was powered by one 24-pin connector. An ATX power supply provides a number of peripheral power connectors and (in modern systems) two connectors for the motherboard: a 8-pin auxiliary connector providing additional power to the CPU and a main 24-pin power supply connector, an extension of the original 20-pin version. 20-pin MOLEX 39-29-9202 at the motherboard. 20-pin MOLEX 39-01-2200 at the cable. The connector pin pitch is 4.2 mm (one sixth of an inch).
Pinouts of ATX 2.x motherboard power connectors, 24-pin (top) and four-pin "P4" (bottom), as viewed into mating side of the plugs[11]
ATX 20-PIN
24-pin ATX power plug; pins 11, 12, 23 and 24 form a detachable separate four-pin plug, making it backward-compatible with 20-pin ATX receptacles
24-pin ATX12V 2.x power supply connector
Color
Signal[A]
Pin[B]
Pin[B][C]
Signal[A]
Color
Orange +3.3 V 1 13 +3.3 V Orange
+3.3 V sense[D] Brown
Orange +3.3 V 2 14 −12 V Blue
Black Ground 3 15 Ground Black
Red +5 V 4 16 Power on[E] Green
Black Ground 5 17 Ground Black
Red +5 V 6 18 Ground Black
Black Ground 7 19 Ground Black
Grey Power good[F] 8 20 Reserved[G] None
Purple +5 V standby 9 21 +5 V Red
Yellow +12 V 10 22 +5 V Red
Yellow +12 V 11 23 +5 V Red
Orange +3.3 V 12 24 Ground Black
^ Jump up to: a b Light-blue background denotes control signals.
^ Jump up to: a b Light-green background denotes the pins present only in the 24-pin connector.
Jump up ^ In the 20-pin connector, pins 13–22 are numbered 11–20 respectively.
Jump up ^ Supplies +3.3 V power and also has a second low-current wire for remote sensing.[12]
Jump up ^ A control signal that is pulled up to +5 V by the PSU and must be driven low to turn on the PSU.
Jump up ^ A control signal that is low when other outputs have not yet reached, or are about to leave, correct voltages.
Jump up ^ Formerly −5 V ( white wire), absent in modern power supplies; it was optional in ATX and ATX12V v1.2 and deleted since v1.3.
Molex connector part numbers
Pins
Female/receptacle
on PS cable
Male/vertical header
on PCB
Male/plug
extender cable
4-pin 39-01-2040 39-28-1043 39-01-2046
20-pin 39-01-2200 39-28-1203 39-01-2206
24-pin 39-01-2240 39-28-1243 39-01-2246
Four wires have special functions:
PS_ON# (power on) is a signal from the motherboard to the power supply. When the line is connected to ground (by the motherboard), the power supply turns on. It is internally pulled up to +5 V inside the power supply.[2][13]
PWR_OK ("power good") is an output from the power supply that indicates that its output has stabilized and is ready for use. It remains low for a brief time (100–500 ms) after the PS_ON# signal is pulled low.[14]
+5 VSB (+5 V standby) supplies power even when the rest of the supply wire lines are off. This can be used to power the circuitry that controls the power-on signal.
+3.3 V sense should be connected to the +3.3 V on the motherboard or its power connector. This connection allows remote sensing of the voltage drop in the power-supply wiring. Some manufacturers also provided a +5 V sense wire (typically colored pink) connected to one of the red +5 V wires on some models of power supply, however, the inclusion of such wire was a non-standard practice and was never part of any official ATX standard.
Generally, supply voltages must be within ±5% of their nominal values at all times. The little-used negative supply voltages, however, have a ±10% tolerance. There is a specification for ripple in a 10 Hz–20 MHz bandwidth:[2]
Supply (V)
Tolerance
Range, min. to max. (V)
Ripple, p. to p., max. (mV)
+5 ±5% (±0.25 V) +4.75 V to +5.25 050
−5 ±10% (±0.50 V) −4.50 V to −5.50 050
+12 ±5% (±0.60 V) +11.40 V to +12.60 120
−12 ±10% (±1.20 V) −10.80 V to −13.20 120
+3.3 ±5% (±0.165 V) +3.135 V to +3.465 050
+5 standby ±5% (±0.25 V) +4.75 V to +5.25 050
The 20–24-pin Molex Mini-Fit Jr. has a power rating of 600 volts, 8 amperes maximum per pin (while using 18 AWG wire).[15] As large server motherboards and 3D graphics cards have required progressively more and more power to operate, it has been necessary to revise and extend the standard beyond the original 20-pin connector, to allow more current using multiple additional pins in parallel. The low circuit voltage is the restriction on power flow through each connector pin; at the maximum rated voltage, a single Mini-Fit Jr pin would be capable of 4800 watts.
Physical characteristics[edit]
ATX power supplies generally have the dimensions of 150 × 86 × 140 mm (5.9 × 3.4 × 5.5 in),[16]:23–24 with the width and height being the same as the preceding LPX (Low Profile eXtension) form factor (which are often incorrectly referred to as "AT" power supplies due to their ubiquitous use in later AT and Baby AT systems, even though the actual AT power supply form factor was physically larger) and share a common mounting layout of four screws arranged on the back side of the unit. That last dimension, the 140 mm depth, is frequently varied, with depths of 160, 180, 200 and 230 mm used to accommodate higher power or modular connectors.
Main changes from AT and LPX designs[edit]
Power switch[edit]
Original AT cases (flat case style) had an integrated power switch that protruded from the power supply and sat flush with a hole in the AT chassis. It utilized a paddle-style DPST switch and was similar to the PC and PC-XT style power supplies.
Later AT (so-called "Baby AT") and LPX style computer cases had a power button that was directly connected to the system computer power supply (PSU). The general configuration was a double-pole latching mains voltage switch with the four pins connected to wires from a four-core cable. The wires were either soldered to the power button (making it difficult to replace the power supply if it failed) or blade receptacles were used.
Typical ATX 1.3 power supply. From left to right, the connectors are 20-pin motherboard, 4-pin "P4 connector", fan RPM monitor (note the lack of a power wire), SATA power connector (black), "Molex connector" and floppy connector.
Interior view in an ATX power supply
An ATX power supply is typically controlled by an electronic switch connected to the power button on the computer case and allows the computer to be turned off by the operating system. In addition, many ATX power supplies have an equivalent-function manual switch on the back that also ensures no power is being sent to the components. When the switch on the power supply is turned off, however, the computer cannot be turned on with the front power button.
Power connection to the motherboard[edit]
The power supply's connection to the motherboard was changed from the older AT and LPX standards; AT and LPX had two similar connectors that could be accidentally interchanged by forcing the different keyed connectors into place, usually causing short-circuits and irreversible damage to the motherboard (the rule of thumb for safe operation was to connect the side-by-side connectors with the black wires together). ATX used one large, keyed connector which could not be connected incorrectly. The new connector also provides a 3.3 volt source, removing the need for motherboards to derive this voltage from the 5 V rail. Some motherboards, particularly those manufactured after the introduction of ATX but while LPX equipment was still in use, supported both LPX and ATX PSUs.[17]
If using an ATX PSU for purposes other than powering an ATX motherboard, power can be fully turned on (it is always partly on to operate "wake-up" devices) by shorting the "power-on" pin on the ATX connector (pin 16, green wire) to a black wire (ground), which is what the power button on an ATX system does. At least the specified minimum load required by the PSU should be present; the standard does not specify operation without load and a conforming PSU may shut down, output incorrect voltages, or otherwise malfunction, but will not be hazardous or damaged.
Airflow[edit]
The original ATX specification called for a power supply to be located near to the CPU with the power supply fan drawing in cooling air from outside the chassis and directing it onto the processor. It was thought that in this configuration, cooling of the processor would be achievable without the need of an active heatsink.[2] This recommendation was removed from later specifications; modern ATX power supplies usually exhaust air from the case.
ATX power supply revisions[edit]
Original ATX[edit]
ATX, introduced in late 1995, defined three types of power connectors:
4-pin "Molex connector" — transferred directly from AT standard: +5 V and +12 V for P-ATA hard disks, CD-ROMs, 5.25 inch floppy drives and other peripherals.[18]
4-pin Berg floppy connector — transferred directly from AT standard: +5 V and +12 V for 3.5 inch floppy drives and other peripherals.[19]
20-pin Molex Mini-fit Jr. main motherboard connector — new to the ATX standard.
A supplemental 6-pin AUX connector providing additional 3.3 V and 5 V supplies to the motherboard, if needed. This was used to power the CPU in motherboards with CPU voltage regulator modules which required 3.3 volt and/or 5 volt rails and could not get enough power through the regular 20-pin header.
The power distribution specification defined that most of the PSU's power should be provided on 5 V and 3.3 V rails, because most of the electronic components (CPU, RAM, chipset, PCI, AGP and ISA cards) used 5 V or 3.3 V for power supply. The 12 V rail was only used by fans and motors of peripheral devices (HDD, FDD, CD-ROM, etc.)
ATX12V 1.x[edit]
While designing the Pentium 4 platform in 1999/2000, the standard 20-pin ATX power connector was found insufficient to meet increasing power-line requirements; the standard was significantly revised into ATX12V 1.0 (ATX12V 1.x is sometimes inaccurately called ATX-P4). ATX12V 1.x was also adopted by AMD Athlon XP and Athlon 64 systems. However, some early model Athlon XP and MP boards (including some server boards) and later model lower-end motherboards do not have the 4-pin connector as described below.
Numbering of the ATX revisions may be a little confusing: ATX refers to the design, and goes up to version 2.2 in 2004 (with the 24 pins of ATX12V 2.0) while ATX12V describes only the PSU. For instance, ATX 2.03 is pretty commonly seen on PSU from 2000 & 2001 and often include the P4 12V connector, even if the norm itself does not define it yet![2]
ATX12V 1.0[edit]
The main changes and additions in ATX12V 1.0 (released in February 2000) were:
Increased the power on the 12 V rail (power on 5 V and 3.3 V rails remained mostly the same).
An extra 4-pin mini fit JR (Molex 39-01-2040), 12-volt connector to power the CPU.[16]
Formally called the +12 V Power Connector, this is commonly referred to as the P4 connector because this was first needed to support the Pentium 4 processor.
Before the Pentium 4, processors were generally powered from the 5 V rail. Later processors operate at much lower voltages, typically around 1 V and some draw over 100 A. It is infeasible to provide power at such low voltages and high currents from a standard system power supply, so the Pentium 4 established the practice of generating it with a DC-to-DC converter on the motherboard next to the processor, powered by the 4-pin 12 V connector.
ATX12V 1.1[edit]
This is a minor revision from August 2000. The power on the 3.3 V rail was slightly increased and other smaller changes were made.
ATX12V 1.2[edit]
A relatively minor revision from January 2002. The only significant change was that the −5 V rail was no longer required (it became optional). This voltage was required by the ISA bus, which is no longer present on almost all modern computers.
ATX12V 1.3[edit]
Introduced in April 2003 (a month after 2.0). This standard introduced some changes, mostly minor. Some of them are:
Slightly increased the power on 12 V rail.
Defined minimal required PSU efficiencies for light and normal load.
Defined acoustic levels.
Introduction of Serial ATA power connector (but defined as optional).
Guidance for the −5 V rail was removed (but it was not prohibited).[20]
ATX12V 2.x[edit]
ATX12V 2.x brought a very significant design change regarding power distribution. By analyzing the power demands of then-current PCs, it was determined that it would be much cheaper and more practical to power most PC components from 12 V rails, instead of from 3.3 V and 5 V rails.
In particular, PCI Express expansion cards take much of their power from the 12 V rail (up to 5.5 A), while the older AGP graphics cards took only up to 1 A on 12 V and up to 6 A on 3.3 V. The CPU is also driven by a 12 V rail, while it was done by a 5 V rail on older PCs (before the Pentium 4).
ATX12V 2.0[edit]
ATX-450PNF by FSP Group
The power demands of PCI Express were incorporated in ATX12V 2.0 (introduced in February 2003), which defined quite different power distribution from ATX12V 1.x:
Most power is now provided on 12 V rails. The standard specifies that two independent 12 V rails (12 V2 for the four-pin connector and 12 V1 for everything else) with independent overcurrent protection are needed to meet the power requirements safely (some very high power PSUs have more than two rails, recommendations for such large PSUs are not given by the standard).
The power on 3.3 V and 5 V rails was significantly reduced.
The main ATX power connector was extended to 24 pins. The extra four pins provide one additional 3.3 V, 5 V and 12 V circuit.
The six-pin AUX connector from ATX12V 1.x was removed because the extra 3.3 V and 5 V circuits which it provided are now incorporated in the 24-pin main connector.
The power supply is required to include a Serial ATA power cable.
Many other specification changes and additions
ATX12V v2.01[edit]
This is a minor revision from June 2004. An errant reference for the −5 V rail was removed. Other minor changes were introduced.[21]
ATX12V v2.1[edit]
This is a minor revision from March 2005. The power was slightly increased on all rails. Efficiency requirements changed.
ATX12V v2.2[edit]
Also released in March 2005[2] it includes corrections and specifies High Current Series wire terminals for 24-pin main and 4-pin +12 V power connectors.
ATX12V v2.3[edit]
Effective March 2007. Recommended efficiency was increased to 80% (with at least 70% required) and the 12 V minimum load requirement was lowered. Higher efficiency generally results in less power consumption (and less waste heat) and the 80% recommendation brings supplies in line with new Energy Star 4.0 mandates.[22] The reduced load requirement allows compatibility with processors that draw very little power during startup.[23] The absolute over-current limit of 240 VA per rail was removed, allowing 12 V lines to provide more than 20 A per rail.[citation needed]
ATX12V v2.31[edit]
This revision became effective on February 2008. It added a maximum allowed ripple/noise specification of 400 millivolts to the PWR_ON and PWR_OK signals, requires that the DC power must hold for more than 1 millisecond after the PWR_OK signal drops, clarified country-specific input line harmonic content and electromagnetic compatibility requirements, added a section about Climate Savers, updated recommended power supply configuration charts, and updated the cross-regulation graphs.
ATX12V v2.32[edit]
This the unofficial name given to the later revisions of the v2.31 spec.[24]
ATX12V v2.4[edit]
This is the current version of the ATX12V spec, published in April 2013. It is specified in Revision 1.31 of the 'Design Guide for Desktop Platform Form Factors', which names this as ATX12V version 2.4.[25]
ATX power supply derivatives[edit]
SFX[edit]
An SFX power supply unit
SFX is merely a design for a power supply casing, with the power specifications almost identical to ATX. Thus, an SFX power supply is mostly pin-compatible with the ATX power supply as the main difference is its reduced dimensions; the only electrical difference is that the SFX specifications do not require the −5 V rail. Since −5 V is required only by some ISA-bus expansion cards, this is not an issue with modern hardware and decreases productions costs. As a result, ATX pin 20, which carried −5 V, is absent in current power supplies; it was optional in ATX and ATX12V version 1.2 and deleted as of ATX version 1.3.
SFX has dimensions of 125 × 100 × 63.5 mm (width × depth × height), with a 60 mm fan, compared with the standard ATX dimensions of 150 × 86 × 140 mm. Optional 80 or 40 mm fan replacement increases or decreases the height of an SFX unit.[26]
Some manufacturers and retailers incorrectly market SFX power supplies as µATX or MicroATX power supplies.[citation needed]
TFX[edit]
A TFX power supply unit
Another small power supply design with standard ATX specification connectors. Generally 5.75×3.25×2.5 in (D) × (W) × (H) (146×83×64 mm).
WTX[edit]
Provides a WTX style motherboard connector which is incompatible with the standard ATX motherboard connector.
AMD GES[edit]
This is an ATX12V power supply derivative made by AMD to power its Athlon MP (dual processor) platform. It was used only on high-end Athlon MP motherboards. It has a special 8-pin supplemental connector for motherboard, so an AMD GES PSU is required for such motherboards (those motherboards will not work with ATX(12 V) PSUs).
a. ATX12V-GES 24-pin P1 motherboard connector. The pinout on the motherboard connector is as follows when viewing the motherboard from above:
Pin
Signal
Colour
Pin
Signal
Colour
12 12 V Yellow 24 12 V Yellow
11 12 V Yellow 23 GND Black
10 GND Black 22 GND Black
9 GND Black 21 3.3 V Orange
8 3.3 V Orange 20 3.3 V Orange
7 3.3 V Orange 19 3.3 V Orange
6 GND Black 18 GND Black
5 PS_ON_N Green 17 −12 V Blue
4 GND Black 16 5 V SB Purple
3 GND Black 15 GND Black
2 5 V Red 14 5 V Red
1 5 V Red 13 5 V Red
b. ATX12V-GES 8-pin P2 motherboard connector. This pinout on the motherboard connector is as follows when viewing the motherboard from above:
Pin
Signal
Colour
Pin
Signal
Colour
4 GND Black 8 12 V Yellow striped black
3 GND Black 7 12 V Yellow striped black
2 PWR_OK Gray 6 12 V Yellow striped black
1 5 V Red 5 GND Black
EPS12V[edit]
EPS12V is defined in Server System Infrastructure (SSI) and used primarily by SMP/multi-core systems such as Core 2, Core i7, Opteron and Xeon. It has a 24-pin main connector (same as ATX12V v2.x), an 8-pin secondary connector and an optional 4-pin tertiary connector. Rather than include the extra cable, many power supply makers implement the 8-pin connector as two combinable 4-pin connectors to ensure backwards compatibility with ATX12V motherboards.
Recent specification changes and additions[edit]
High-performance video card power demands dramatically increased during the 2000s and some high-end graphics cards have power demands that exceed AGP or PCIe slot capabilities. For these cards, supplementary power was delivered through a standard 4-pin peripheral or floppy power connector. Midrange and high-end PCIe graphics cards manufactured after 2004 typically use a standard 6 or 8-pin PCIe power connector directly from the PSU.
Interchanging PSUs[edit]
Although the ATX power supply specifications are mostly vertically compatible in both ways (both electrically and physically), there are potential issues with mixing old motherboards/systems with new PSUs and vice versa. The main issues to consider are the following:
The power allocation between 3.3 V, 5 V and 12 V rails is very different between older and newer ATX PSU designs, as well as between older and newer PC system designs.
Older PSUs may not have connectors which are required for newer PC systems to properly operate.
Newer systems generally have higher power requirements than older systems.
This is a practical guidance what to mix and what not to mix:
Older systems (before Pentium 4 and Athlon XP platforms) were designed to draw most power from 5 V and 3.3 V rails.
Because of the DC-DC converters on the motherboard that convert 12 V to the low voltages required by the Intel Pentium 4 and AMD Athlon XP (and subsequent) processors, such systems draw most of their power from the 12 V rail.
Original ATX PSUs have power distribution designed for pre-P4/XP PCs. They lack the supplemental 4-pin 12-volt CPU power connector, so they most likely cannot be used with P4/XP or newer motherboards. Adapters do exist but power drain on the 12 V rail must be checked very carefully. There is a chance it can work without connecting the 4-pin 12 V connector, but caution is advised.[27]
ATX12V 1.x PSUs have power distribution designed for P4/XP PCs, but they are also greatly suitable for older PCs, since they give plenty of power (relative to old PCs' needs) both on 12 V and on 5 V/3.3 V. It is not recommended to use ATX12V 1.x PSUs on ATX12V 2.x motherboards because those systems require much more power on 12 V than ATX12V 1.x PSUs provide.
ATX12V 2.x PSUs have power distribution designed for late P4/XP PCs and for Athlon 64 and Core Duo PCs. They can be used with earlier P4/XP PCs, but the power distribution will be significantly suboptimal, so a more powerful ATX12V 2.0 PSU should be used to compensate for that discrepancy. ATX12V 2.x PSUs can also be used with pre-P4/XP systems, but the power distribution will be greatly suboptimal (12 V rails will be mostly unused, while the 3.3 V/5 V rails will be overloaded), so this is not recommended.
Systems that use an ISA bus should have a PSU that provides the −5 V rail, which became optional in ATX12V 1.2 and was subsequently phased out by manufacturers.
Some proprietary brand-name systems require a matching proprietary power supply, but some of them may also support standard and interchangeable power supplies.
Efficiency[edit]
See also: Green computing and 80 Plus
Efficiency in power supplies means the extent to which power is not wasted in converting electricity from a household supply to regulated DC. Computer power supplies vary from around 70% to over 90% efficiency.
Various initiatives exist to improve the efficiency of computer power supplies. Climate Savers Computing Initiative promotes energy saving and reduction of greenhouse gas emissions by encouraging development and use of more efficient power supplies. 80 PLUS certifies a variety of efficiency levels for power supplies and encourages their use via financial incentives. Efficient power supplies also save money by wasting less power; as a result they use less electricity to power the same computer, and they emit less waste heat which results significant energy savings on central air conditioning in the summer. The gains of using an efficient power supply are more substantial in computers that use a lot of power.
Although a power supply with a larger than needed power rating will have an extra margin of safety against overloading, such a unit is often less efficient and wastes more electricity at lower loads than a more appropriately sized unit. For example, a 900-watt power supply with the 80 Plus Silver efficiency rating (which means that such a power supply is designed to be at least 85-percent efficient for loads above 180 W) may only be 73% efficient when the load is lower than 100 W, which is a typical idle power for a desktop computer. Thus, for a 100 W load, losses for this supply would be 37 W; if the same power supply was put under a 450 W load, for which the supply's efficiency peaks at 89%, the loss would be only 56 W despite supplying 4.5 times the useful power.[28][29] For a comparison, a 500-watt power supply carrying the 80 Plus Bronze efficiency rating (which means that such a power supply is designed to be at least 82-percent efficient for loads above 100 W) may provide an 84-percent efficiency for a 100 W load, wasting only 19 W.[30]
See also[edit]
Computing portal
Electronics portal
AT (form factor)
BTX (form factor)
Computer form factor
Mini-ITX
Power supply unit (computer)
SSI CEB
References[edit]
Jump up ^ Mark, Soper; Prowse, David; Mueller, Scott (September 2012). Authorized Cert Guide: CompTIA A+. Pearson Education. ISBN 978-0-7897-4850-8.
^ Jump up to: a b c d e "ATX Specification - Version 2.2" (PDF). Retrieved April 4, 2014.
Jump up ^ "Power Supply Design Guide for Desktop Platform Form Factors" (PDF). February 2008. Retrieved April 4, 2014.
Jump up ^ Scott Mueller, Upgrading and Repairing PCs, Eleventh Edition, Que Books, 1999, ISBN 0-7897-1903-7, page 1255
Jump up ^ "Foxconn F1 Motherboard Prototype". Hardwaresecrets.com. Archived from the original on 24 October 2014. Retrieved 18 November 2014.
Jump up ^ Thomas Soderstrom. "Foxconn Reveals X48, Ultra ATX, and Shamino". Tom's Hardware. Retrieved 18 November 2014.
Jump up ^ "Lian Li Armorsuit PC-P80R Spider Edition". TechPowerUp. Retrieved 18 November 2014.
Jump up ^ "The New 4-Way SLI Platform Has Arrived!". Evga.com. Retrieved 18 November 2014.
Jump up ^ "EVGA Corporation Super Record 2". Evga.com. Retrieved 18 November 2014.
Jump up ^ "Console Hacking 2016 – PS4: PC Master Race". 2016-12-27.
Jump up ^ "Power Supply Design Guide for Desktop Platform Form Factors, Revision 1.31" (PDF). Intel. April 2013. p. 26. Archived from the original (PDF) on October 21, 2014. Retrieved February 6, 2015.
Jump up ^ "ATX Specification Version 2.1" (PDF).
Jump up ^ "How to Convert a Computer ATX Power Supply to a Lab Power Supply (with video) - wikiHow". Retrieved 2013-08-17. wikihow.com
Jump up ^ "PCGuide - Ref - Power Supply - Functions". Retrieved 2013-08-17. pcguide.com
Jump up ^ "Mini-Fit Jr.™ Power Connectors - Molex". Molex.com. Retrieved 18 November 2014.
^ Jump up to: a b "AT / ATX12V Power Supply Design Guide Version 1.1". Intel Corporation. August 2000. p. 28. Archived from the original (pdf) on 2011-03-11. Retrieved 2011-03-11.
Jump up ^ "Example of a motherboard that can support connecting AT and ATX PSUs". Createch.com. Retrieved 18 November 2014.
Jump up ^ "PC peripheral power connector pinout and signals @ pinouts.ru". Pinouts.ru. Retrieved 18 November 2014.
Jump up ^ "PC floppy power connector pinout and signals @ pinouts.ru". Pinouts.ru. Retrieved 18 November 2014.
Jump up ^ "ATX12V Power Supply Design Guide Version 1.3" (pdf). Intel Corporation. April 2003. p. 38. Retrieved 2013-03-24.
Jump up ^ "ATX12V Power Supply Design Guide Version 2.01" (pdf). Intel Corporation. June 2004. p. 44. Retrieved 2013-03-24.
Jump up ^ "Design Guide for Desktop Platform Form Factors, Intel Corp" (PDF). Formfactors.org. Retrieved 18 November 2014.
Jump up ^ "#138 - Question/Answer: ATX 12V 2.2 vs. ATX 12V 2.3". YouTube. Retrieved 18 November 2014.
Jump up ^ https://www.techpowerup.com/reviews/Antec/HCG-750M/2.html
Jump up ^ "Power Supply Design Guide for Desktop Platform Form Factors" (PDF). Intel. April 2013. Archived (PDF) from the original on April 1, 2018. Retrieved April 1, 2018.
Jump up ^ "SFX Form Factor". Pcguide.com. Retrieved 18 November 2014.
Jump up ^ [1] Archived October 3, 2009, at the Wayback Machine.
Jump up ^ Christoph Katzer (2008-09-22). "Debunking Power Supply Myths". AnandTech. p. 3. Retrieved 2014-10-07.
Jump up ^ "Cooler Master UCP Product Sheet" (PDF). Cooler Master. 2008. Retrieved 2014-10-11.
Jump up ^ Martin Kaffei (2011-10-10). "SilverStone Strider Plus – 500 W Modular Power". AnandTech. p. 4. Retrieved 2014-10-11.
External links[edit]
Wikimedia Commons has media related to Computer motherboards.
ATX Motherboard Specifications
ATX Motherboard Specification, v1.1
ATX Motherboard Specification, v2.2
ATX Power Supply Specifications
ATX12V Power Supply Design Guide, v2.01
ATX12V Power Supply Design Guide, v2.2
ATX12V Power Supply Design Guide, v2.3 (Power Supply Design Guide for Desktop Platform Form Factors, v1.1)
ATX12V Power Supply Design Guide, v2.31 (Power Supply Design Guide for Desktop Platform Form Factors, v1.2)
ATX12V Power Supply Design Guide, v2.4 (Power Supply Design Guide for Desktop Platform Form Factors, v1.31)
EPS Power Supply Specifications
EPS12V Power Supply Design Guide, v2.0
EPS12V Power Supply Design Guide, v2.91
EPS12V Power Supply Design Guide v2.92
Other
Power Supply Form Factors
Various power supply cables and connectors
A short history of power supply voltage rails
ATX power supply connectors with pinouts
More ATX power supply connectors with pinouts
ATX Power Supply Terminology
Retrieved from "https://en.wikipedia.org/w/index.php?title=ATX&oldid=833579118"
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