Bit OT, but: I wouldn't bother with the GTX295. Being a dual-GPU card, you can expect anything from 10 to 60% (maybe little more) in performance gain (compared to same single GPU), but it really depends on the game. Far too unpredictable imho. And it's powerhungry, quite a bit more so than the 5770. Another strike against it is that it has 896MB effectively, compared to 1024MB on the radeon.
TBH, I'd wait and see what Nvidia is coming up with early next year. At this point you "should" buy the Radeon 5770/5750, but only because of a lack of competition.
*meant the 58xx offcourse, 5700 series is out so I'm confused.
