GTX295 psu help

ferny12345623

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Mar 1, 2009
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hey guys i moved my system from a atx case to a itx case. i have a silverstone SG05bb-450 (450 watt psu) and i was wondering if the 450 watt psu would power the gtx 295. full specs i7 2600k 8gb ddr3 1333 64GB ssd boot drive 500GB seagate momentus xt blu-ray drive and gtx295 and mobo is zotac z68 itx. and a corsair nautilus 500 yes you read that right, i got a new one and having used one in the past i know it cools good.. getting back to the point with the psu power everthing????im willing to use a external octical drive to save some energy
 

ferny12345623

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Mar 1, 2009
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18,690
well that sucks, i really like my 295 and my itx case, i would hate to buy another video card. i've been looking at some psu calculators and it looks like i would draw 458 watts total based on whats going in the pc. i figured that 8 watts is not much to worry about do to the psu is a 80 plus certified. i read the link you gave me and it also state under load with a i7 960 which uses alot more power than my 2600k it was using a total of 416 watts. any other thoughts?
 

beenthere

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It's not 8W that is the issue. It's how many amps are available on the 12v rail(s).

According to Nvidia the card draws 289W or ~24 amps. You'll need at least 15 amps for the rest of the PC. So at the very least you should have 45 amps. on the 12v rail as that leaves you only a 13% safety factor for heat build-up and drop in efficiency. What is the 12v rail in amps. on your PSU ?