If you want an efficient high-quality PSU, I recommend this one for comfortably powering 8 Klondikes:
http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=7580853&CatId=2533
http://www.hardwaresecrets.com/article/XFX-PRO-750-W-Black-Edition-Full-Modular-Power-Supply-Review/1695/13

Up to 92% efficient, fully modular, and top quality (Seasonic KM3 core). Watch out for similarly named older products that aren't as good.