The GTX 460 is pretty much always faster than the 5770.
It is faster than the 5830 in everything but the Source engine (not that it is slow in the Source engine, we're still talking 100+ FPS). You really don't want a 5830 though because it is a very cut down 5870 that keeps the heat and noise without keeping the performance.
Ah...nice thanks! So in theory I should have asked more of a comparison with the 460 vs 5870 ;-) haha...My guess is though that the 460 will still top the 5870...
I found a deal on HDD's (Four 1.5TB's) and a i7 - just under $400 for all 5 so that's not a bad deal.