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. Original AT cases (flat case style) have an integrated power switch that protruded from the power supply and

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 in 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. We waited years for a competitor to dethrone Corsair's AX1500i, and in the end it was another Corsair power supply to post higher overall performance. The Corsair AX1600i is the best PSU that money can buy today, period. It offers top performance in all areas and uses an innovative platform, which provides a glimpse at the future of power supply design. The ATX motherboard connector was extended to 24 pins. The extra four pins provide one additional 3.3V, 5V and 12V circuit.

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Clearance is an important consideration in any PC build, and it isn’t any less so here. Larger cases have more clearance for fans, liquid cooling, and other components. You’ll also need to keep in mind the graphics card you plan to use, as these can get rather long, and not every graphics card will fit every case.

Also released in March 2005 [3] it includes corrections and specifies High Current Series wire terminals for 24-pin ATX motherboard and 4-pin +12V power connectors.

Thomas Soderstrom (13 January 2008). "Foxconn Reveals X48, Ultra ATX, and Shamino". Tom's Hardware . Retrieved 18 November 2014.