Corsair HX750 PSU

stevex033

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Aug 27, 2010
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So I am thinking about buying a Corsair HX750 but I dunno if it can power my computer. I did a psu calculator and it says 831 w would be safe. But when I asked the build area about my build they said that psu should be able to handle it.

Estimated Specs:

Asus p8p67 PRo
i5-2500k overclocked
g.skill mem 8gb 1600 cas 9
spinpoint f3
asus gtx 570 plus 1 later
nzxt phantom white
corsair hx750
asus dvd drive

SO will that psu power the sli configuration when I get the second card or should I look for a different psu

thanks,

steve
 

bigbang

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Jun 4, 2004
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when considering the psu, also consider that their power output decreases year by year by about 5%, also if u are overclocking, which i suggest u do, then the power output will be higher than calculated, so to be safe, i would suggest an 850w
 
Power output does not decrease by anywhere near 5%, unless it is a bad PSU or if it is stressed to 100% frequently. The Corsair HX750 is not a bad PSU and it wouldn't be stressed to 100% ever in a system with two 570s.

http://www.guru3d.com/article/geforce-gtx-570-sli-review/13
This shows a system with an i7-965 (which is more power hungry than an i5-2500K, probably even when overclocked) using 578W at the wall when running furmark, which does not place a realistic load on GPUs. So the actual system power draw for them would be 10-20% less. So a likely worst case for your system will be 520W.
A 520W load would stress a 750W PSU to ~70%. So I think it is justifiable to get an 850W PSU.

Altho I think it is more likely to be 460 or even less. And the typical/average load is likely to be lower than that again. A 460W load would only stress a 750W PSU to ~62%.
 

bigbang

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thats very expert advice on psu aging lol, but as a physicist i admit any model will be hugely subject to enviromental effects. i was just giving a random number as to how much to expect it to decrease over its lifetime but i admit i was a bit over the top, i should have said 5-10% over its 4-5 years lifetime