Can it be done, yes. Would you want to, not ever, not a snow balls chance in hell. Not enough power and definitely not even close to enough VRAM. If you want to do surround gaming you want to have at least 2-3GB of VRAM. Preferably 3GB. So the Only cards you would want to use is the GTX570 HD 2.5GB or GTX580 3GB cards in SLI.
Reason being is the bigger the resolution the more power you need to feed the picture and the more memory it takes to map the picture. Especially when you start to add AA and AF.
Tell you friend not to waste his money. He will not be pleased one bit with the performance.