The XFX ProSeries 650W PSU is mostly modular, with only the ATX connector attached, has a 135mm cooling fan and can send 98% of its total wattage to the single 53A 12V rail.  With four 6+2 PCIe power connectors you will be able to handle multiple GPUs and the 8 SATA connectors should allow you as many storage devices as you need.  Unfortunately [H]ard|OCP discovered something about the 5 year warranty which greatly displeased them; unless you register your PSU within 30 days of purchase, you only receive a 2 year warranty.  If you are strictly concerned about the quality of the power this PSU delivers and are ambivalent towards the warranty, this PSU passed [H]'s torture tests handily which is something not every PSU can claim.

"XFX has long and actually very solid history of producing high quality enthusiast power supplies. We have consistently found XFX PSUs worthy of [H] Editor's Choice Awards. Today the XFX ProSeries 650W promises "One Rail, One Setup" in a PSU that is different. Let's see if that is good or bad."

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