looking to replace my 550w ocz fatuity as its powering a i7 930 and soon to be 7970 i think a 600w would cover me. right? i have found two i like the look of (cheep) http://www.scan.co.uk/products/600w...ronze-sli-crossfire-eps-12v-quiet-fan-atx-psu or http://www.scan.co.uk/products/600w...s-sli-crossfire-eps-12v-quiet-fan-atx-v23-psu running low on money so cheaper the better as a 7970 isn't a cheap card(even tho its second hand)
If you want modular http://www.scan.co.uk/products/630w...bronze-sli-crossfire-eps-12v-quiet-fan-atx-ps
A bit more expensive, but it's the best of the best: http://www.scan.co.uk/products/450w-seasonic-g-450-80-plus-gold-rps-12v-modular-atx-psu And yeah, 450W is plenty for any single GPU system.
I'm not so sure of that... My current build (A bit last generation) Of a Phenom 2 X6, 6970, Sivlerstone FT02, and a few other bits and bobs, draws 550W at peak. Whilst I do think that generally PSU capacity is often overdone, I'd suggest 600W-800W for a high end single GPU build. Still leaves space to upgrade to more later. So my suggestion would be a: http://www.scan.co.uk/products/650w...ified-85-efficiency-140mm-fan-5-year-warranty My 4 year old OCZ power supply is still going well, and not a hint of coil whine. They seem to make good stuff. Whilst it's not Gold rated, that seldom makes a difference. I also think a 450W would be at a higher load, and therefore less efficient, ie- Gold 450W at 95% capacity is going to be less efficient than a 650W at 75%.
Really? How did you measure that? The reviews linked in the other thread show that overclocked high end systems pull 350-400W on full load. Note that idle numbers are much less, and a computer will idle most of the time. Efficiency only drops a couple percent at most between 75% and 100% load.