What would I be better off doing ....

[New2PCs]

Yes but you pointed out the GTX680 has more 3x the amount of cuda cores of a GTX295, the architectures are so different they are not directly comparable. Even though the GTX680 has 3x the amount of cuda cores and is clocked much higher it is not 3x faster by any means. Just making the OP aware of that, even so the GTX680 is still a far superior card as I stated before, it has so much going for it.

Also PCI-E 2.0 is no problem for a GTX680, heck its fine even for GTX690 according to this study

Yeah, seems right to go for a 680,

What would your opinion be on the CPU ? Also need a upgrade ? (QX6700 @ 3.2)

[Raptor156]

Definitely get a GTX 680 over another 295... 295's pretty outdated all around these days. PCI-E 2.0 vs. 3.0 doesn't really matter much. I'm running 2x GTX 680's on a PCI-E 2.0 board.

Yeah, seems right to go for a 680,

What would your opinion be on the CPU ? Also need a upgrade ? (QX6700 @ 3.2)

I don't know what socket boards the QX6700's are in, but if you could upgrade it may not be a bad idea. If you'd have to get a whole new board and CPU, it may not be worth it depending on how much extra cash you have. I remember somewhere there was a test done in Battlefield 3 with a ton of different quad core CPUs and for the most part, the CPU didn't really impact performance much as long as it was a quad core. Other games may see more improvement from a better CPU though.

[Meaker]

With a 680 it would not hurt to go with a nice ivy bridge, no need to break the bank either.