jeremy1183

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Apr 29, 2011
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http://www.guru3d.com/article/geforce-gtx-570-sli-review/13

Take a look at that article. The full system wattage on 570 sli is 578watts on a stress load test with the 570's just pulling 410 watts. Even if your system for some reason requires you to pull 650 (higher than the review) watts on load you still would have a decent amount of head room. I doubt you will pull much higher if even the same as they run a powerful rig.