*Source: DVHardware (
http://www.dvhardware.net/review118_...r_1000w.html)*
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A couple of years ago 500W power supplies were considered very high-end but these days ultra high-end gaming PCs use a lot more power. Dual-core and quad-core processors along with a SLI or CrossFire setup of NVIDIA's GeForce 8800 Ultra or ATI's Radeon HD 2900 series can use a lot of power, especially when these components are all heavily overclocked.
Power supply makers were pretty quick to market power supplies with maximum outputs of 750W, 1000W and even 1200W - even though most people and even most computer enthusiasts don't need so much power.
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