What are you planning to mine SHA-256 or Scrypt?

It make a little bit of difference on what models of cards to buy. The usual debate is between 7950 VS 7970. I would go with a 7950 (cheaper and less wattage).  You will want too minimise your power consumption and go with as few as GPU's as possible. For power supplies you need to look at the amount is 12V amps delivered not total wattage. GPU's eat amps like crazy. A good 850 supply Corsair Bronze will drive 2-3 7950's or 2 7970.

MrBSmith

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