The ATX (for Advanced Technology Extended) form factor was created by Intel in 1995. It was the first big change in computer case and motherboard design in many years. ATX overtook AT completely as the default form factor for new systems. ATX addressed many of the AT form factor's annoyances that had frustrated system builders. Other standards for smaller boards (including microATX, FlexATX and mini-ITX) usually keep the basic rear layout but reduce the size of the board and the number of expansion slot positions. In 2003, Intel announced the new BTX standard, intended as a replacement for ATX. As of January 2007 the ATX form factor remains the industry standard for do-it-yourselfers; BTX has however made inroads into pre-made systems, being adopted by computer makers like Dell, Gateway, and HP. A motherboard is the central or primary circuit board making up a complex electronic system, such as a modern computer. ... Intel Corporation (NASDAQ: INTC, SEHK: 4335), founded in 1968 as Integrated Electronics Corporation, is an American multinational corporation that is best known for designing and manufacturing microprocessors and specialized integrated circuits. ... Year 1995 (MCMXCV) was a common year starting on Sunday (link will display full 1995 Gregorian calendar). ... A tower case featuring a modern design. ... A motherboard is the central or primary circuit board making up a complex electronic system, such as a modern computer. ... Baby AT motherboard. ... A8N VM CSM, an ASUS microATX motherboard microATX, also known as µATX (sometimes transliterated as mATX on online forums[1]) is a small form factor standard for computer motherboards, with a maximum size of 244 mm × 244 mm (9. ... FlexATX is a PC motherboard form factor derived from ATX. It is the smallest of the ATX-based form factors. ... Mini-ITX is a low-power motherboard form factor developed by VIA Technologies. ... BTX (for Balanced Technology Extended) is a form factor for PC motherboards, originally slated to be the replacement for the aging ATX motherboard form factor in late 2004 and early 2005. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... BTX (for Balanced Technology Extended) is a form factor for PC motherboards, originally slated to be the replacement for the aging ATX motherboard form factor in late 2004 and early 2005. ... This article is about the corporation Dell, Inc. ... Gateway, Inc. ... The Hewlett-Packard Company (NYSE: HPQ), commonly known as HP, is a very large, global company headquartered in Palo Alto, California, United States. ...

The official specifications were released by Intel in 1995, and have been revised numerous times since, the most recent being version 2.2[1], released in 2004.

A full size ATX board is 12" wide by 9.6" deep (305 mm x 244 mm). This allows many ATX form factor chassis to accept microATX boards as well. A8N VM CSM, an ASUS microATX motherboard microATX, also known as µATX (sometimes transliterated as mATX on online forums[1]) is a small form factor standard for computer motherboards, with a maximum size of 244 mm × 244 mm (9. ...

Power supply

ATX form motherboards became increasingly popular because of their advantages over older AT motherboards.

AT-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. ABIT KT7 PC motherboard, large version, 13 October 2003. ... ABIT KT7 PC motherboard, large version, 13 October 2003. ... Baby AT motherboard. ... The top cover has been removed to show the internals of a computer Power supply Unit. ... A solder is a fusible metal alloy, with a melting point or melting range of 180-190°C (360-370 °F), which is melted to join metallic surfaces, especially in the fields of electronics and plumbing, in a process called soldering. ... A blade connector is a type of single wire connection using a flat blade which is inserted into a receptacle. ...

Typical ATX power supply

An ATX power supply does not directly connect to the system power button, allowing the computer to be turned off via software. However, many ATX power supplies have a manual switch on the back to ensure the computer is truly off and no power is being sent to the components. With this switch on, energy still flows to the components even when the computer appears to be "off." This is known as soft-off or standby and can be used for remote wake up through Wake-on-Ring or Wake-on-LAN, but is generally used to power on the computer through a front switch. Image File history File links Download high-resolution version (1171x859, 309 KB) Other versions Originally from de. ... Image File history File links Download high-resolution version (1171x859, 309 KB) Other versions Originally from de. ... Computer software (or simply software) refers to one or more computer programs and data held in the storage of a computer for some purpose. ... Wake-on-Ring (WOR), sometimes referred to as Wake-on-Modem (WOM), is a specification that allows supported computers and devices to wake up from a soft off state, and begin operation. ... Wake on LAN (WOL, sometimes WoL) is an Ethernet computer networking standard that allows a shut-down computer to be booted remotely. ...

The power supply's connection to the motherboard was changed. Older AT power supplies had two similar connectors that could be accidentally switched, usually causing short-circuits and irreversible damage to the motherboard. ATX used one large, keyed connector instead, making a reversed connection very difficult. The new connector also provided a 3.3 volt source, removing the need for motherboards to derive this voltage from one of the other power rails. Some motherboards, particularly late model AT form factor offerings, supported both AT and ATX PSUs.

ATX was originally designed with the power supply drawing air into the case and exhausting it down onto the motherboard. The plan was to deliver cool air directly to the CPU's and power regulation circuitry's location, which was usually at the top of the motherboard in ATX designs. This was not particularly useful for a variety of reasons. Early ATX systems simply didn't have processors or components with thermal output that required special cooling considerations. Later ATX systems with significantly greater heat output would not be aided in cooling by a power supply delivering its often significantly heated exhaust into the case. As a result, the ATX specification was changed to make PSU airflow optional.[2]

With the introduction of the Pentium 4, the standard 20-pin ATX power connector was deemed inadequate to supply increasing electrical load requirements. The standard was revised with an extra 4-pin, 12-volt connector. This was later adopted by Athlon XP and Athlon 64 systems. Various high-end systems may have other forms of supplemental power connections.

Because video card power demands have dramatically increased over the 2000s, 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 power connector like those used for hard drives or floppy drives. PCI Express-based video cards manufactured after 2004 typically use a standard 6 or 8-pin PCIe power connector directly from the PSU. The Accelerated Graphics Port (also called Advanced Graphics Port, often shortened to AGP) is a high-speed point-to-point channel for attaching a graphics card to a computers motherboard, primarily to assist in the acceleration of 3D computer graphics. ... PCI Express (formerly known as 3GIO for 3rd Generation I/O, not to be mistaken with PCI-X) is an implementation of the PCI computer bus that uses existing PCI programming concepts and communications standards, but bases it on a much faster serial communications system. ...

Because the ATX PSU uses the motherboard's power switch, turning on the power in situations that do not utilize an ATX motherboard is possible by shorting the green wire from the ATX connector to any black wire on the connector (or ground). This allows re-use of an old PC power supply for tasks other than powering a PC, but one must be careful to observe the minimum load requirements of the PSU.

The ATX form factor has had five main power supply designs throughout its lifetime: Form factor refers to the linear dimensions and configuration of a device as distinguished from other measures of size (for example Gigabytes; a measure of storage size): in computing, form factor is used to describe the size and format of PC motherboards (see AT, ATX, BTX), but also of hard...

• ATX - 20 pin connector (Used through Pentium III and early Athlon XP)
• WTX - 24 pin connector (Pentium II and III, Xeon and Athlon MP)
• AMD GES - 24 pin main connector, 8 pin secondary connector (some dual-processor Athlon)
• EPS12V - 24 pin main connector, 8 pin secondary connector, optional 4 pin tertiary connector (Xeon and Opteron) defined in SSI specification
• ATX12V - 20 pin main connector, 4 pin secondary connector, 8 pin tertiary connector (Pentium 4 and mid/late Athlon XP & Athlon 64)
  • ATX12V 1.3 - guidance for the -5 volt feed was removed. This was only used by legacy ISA add-in cards
  • ATX12V 2.0 - 24 pin main connector, 4 pin secondary connector (Pentium 4, Core 2 Duo, and Athlon 64 with PCI Express)
  • ATX12V 2.2 - One 20/24-pin connector, one ATX12V 4 pin connector. Many power supply manufacturers include a 4 plus 4 pin, or 8 to 4 pin secondary connector instead, which can also be used as the secondary EPS12V connector.

Pentium III logo The Pentium III is an x86 (more precisely, an i686) architecture microprocessor by Intel, introduced on February 26, 1999. ... Athlon is the brand name applied to a series of different x86 processors designed and manufactured by AMD. The original Athlon, or Athlon Classic, was the first seventh-generation x86 processor and, in a first, retained the initial performance lead it had over Intels competing processors for a significant... This article is about the Intel microprocessor. ... Athlon is the brand name applied to a series of different x86 processors designed and manufactured by AMD. The original Athlon, or Athlon Classic, was the first seventh-generation x86 processor and, in a first, retained the initial performance lead it had over Intels competing processors for a significant... The Opteron is AMDs x86 server processor line, and was the first processor to implement the AMD64 instruction set architecture (known generically as x86-64). ... The Pentium 4[1] brand refers to Intels single-core mainstream desktop and laptop CPUs introduced on November 20, 2000[2] (August 8, 2008 is the date of last shipments of Pentium 4s[3]). They had the 7th-generation architecture - called NetBurst - which was the companys first all... Athlon is the brand name applied to a series of different x86 processors designed and manufactured by AMD. The original Athlon, or Athlon Classic was the first seventh-generation x86 processor and, in a first, retained the initial performance lead it had over Intels competing processors for a significant... The Athlon 64 is an eighth-generation, AMD64 architecture microprocessor produced by AMD, released on September 23, 2003. ... This article does not cite any references or sources. ... Core 2 Duo brand logo Core 2 Extreme brand logo Core 2 is an eighth-generation x86 architecture microprocessor produced by Intel based on an all-new CPU architecture called the Intel Core Microarchitecture, which is the successor of NetBurst microarchitecture that has powered most Intel processors since 2000. ... PCI Express (formerly known as 3GIO for 3rd Generation I/O, not to be mistaken with PCI-X) is an implementation of the PCI computer bus that uses existing PCI programming concepts and communications standards, but bases it on a much faster serial communications system. ...

Dell power supplies

Older Dell computers, particularly those from the Pentium II and III times, are notable for using proprietary power wiring on their power supplies and motherboards. While the motherboard connectors appear to be standard ATX, and will actually fit a standard power supply, they are not compatible. Not only have wires been switched from one location to another, but the number of wires for a given voltage has been changed. Thus, the pins cannot simply be rearranged.[3] Intel Pentium II Logo The Pentium II is an x86 architecture microprocessor by Intel, introduced on May 7, 1997. ... Pentium III logo The Pentium III is an x86 (more precisely, an i686) architecture microprocessor by Intel, introduced on February 26, 1999. ...

The change affects not only 20-pin ATX connectors, but also auxiliary 6-pin connectors. Modern Dell systems may use standard ATX connectors.[4] Dell PC owners should be careful when attempting to mix non-Dell motherboards and power supplies, as it can cause damage to the power supply or other components. If the power supply color coding on the wiring does not match ATX standards, then it is probably proprietary. Wiring diagrams for Dell systems are usually available on Dell's support page.

Connectors

ATX I/O plates

On the back of the system, some major changes were made. The AT standard only had 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). Generally the case comes with a snap out panel, also known as an I/O plate, reflecting one of the common arrangements. If necessary, I/O plates can be replaced to suit the arrangement on the motherboard that is being fitted and the I/O plates are usually included when purchasing a motherboard. Panels were also made that allowed fitting an AT motherboard in an ATX case. Image File history File links Download high-resolution version (1280x836, 229 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): ATX ... Image File history File links Download high-resolution version (1280x836, 229 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): ATX ... A 104-key PC US English QWERTY keyboard layout The Dvorak Simplified Keyboard layout A standard Hebrew keyboard showing both Hebrew and QWERTY. A computer keyboard is a peripheral partially modelled after the typewriter keyboard. ... A male DE-9 connector used for a serial port on a PC style computer. ... This article is about the Centronics style port. ...

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 a PS/2 mouse ports were also found on some systems). Not to be confused with PlayStation 2. ... The mini-DIN connectors are a family of multi-pin Electrical connectors used in a variety of applications. ... 5 pin 180° DIN connector 4 pin Mini-DIN S-Video connector Speaker DIN line socket (left) and plug DIN connectors are multi-pin electrical connectors based on a DIN standard. ...

But some manufacturers are creating some PSU that might be "compatible" with a Dell case. Antec is providing that kind of model, however you might need to detached the power switch to make it fully compliant. Most of the new Dell PSU are providing without the "white" wire (-5V), so just make sure you are not this one connected. (Antec is without that wire)

Variants

There exist several ATX-derived form factors that use the same power supply, mountings and basic back panel arrangement but set different standards for the size of the board.

FlexATX is a PC motherboard form factor derived from ATX. It is the smallest of the ATX-based form factors. ... A8N VM CSM, an ASUS microATX motherboard microATX, also known as µATX (sometimes transliterated as mATX on online forums[1]) is a small form factor standard for computer motherboards, with a maximum size of 244 mm × 244 mm (9. ...

Computer Power Supply form factors

• ATX
• WTX
• TFX
• SFX
• CFX
• LFX

Motherboard form factor introduced by Intel in 1998, for its use at high-end, multiprocessor, multiple-hard-disks server and workstations. ... A U.S. Air Force F-111 The General Dynamics F-111 Aardvark (the nickname was unofficial for most of its lifespan, but it was officially named Aardvark at its retirement ceremony for the United States Air Force) is a long-range strategic bomber, reconnaissance, and tactical strike aircraft. ... SFX is a three letter acronym for any of the following: Special effects or Sound effects SFX, a sci-fi magazine Spread Firefox, a campaign to encourage the use of Mozilla Firefox SFX, a concert venue in Dublin Self-extracting archive, a compressed file with an embedded executable to decompress... CFX is a commercial computational fluid dynamics (CFD) program widely employed within industry. ...

See also

• mini-ITX
• BTX
• SSI CEB

Mini-ITX is a low-power motherboard form factor developed by VIA Technologies. ... BTX (for Balanced Technology Extended) is a form factor for PC motherboards, originally slated to be the replacement for the aging ATX motherboard form factor in late 2004 and early 2005. ... There are very few or no other articles that link to this one. ...

External links

• ATX Motherboard Specification, v2.2
• Power Supply Form Factors
• ATX12V Power Supply Design Guide, v2.2
• EPS12V Power Supply Design Guide, v2.91
• ATX power supply connectors with pinouts
• ATX Power Supply Links
• More ATX power supply connectors with pinouts
• Motherboard power connectors with pinouts
• ATX Riser Card Specification Revision 1.0