Hi all, So since we didn't see a viable upgrade at WWDC this year, I'm going to stick with my 2.8 Mac Pro and cross fire a couple of 5870s, and later down the road replace its Xeon with an i7x at some point, all to hopefully tie my computing needs over until the 2013 models come out. My question concerning the 5870 cross firing is--while I already have an Apple 5870 installed, could I use a PC version of a 5870 to cross fire them? The difference (of about $200+) is substantial. Also, anyone know of some decent non ECC RAM for the i7x switch in the future? Cheers!