Originally Posted by KG363
I don't think it's worth it unless you get a good price on the GTX 275. I went from a 4890 (roughly same performance as 275) to my Crossfired 5770's and the only reason I did this was because I got them for $60 each. If I didn't get that price I would still have my 4890. I just don't think the upgrade is worth the price
No offense at all, but it's a bit tough to not recommend an upgrade for someone if you personally don't have experience with EITHER card that the OP has/wants.
Yes, a 4890 is roughly the ATI equivalent of the 275. However, a GTX 275 also has only 240 CUDA cores as opposed to the 440 cores of the GTX 470. That is a SUBSTANTIAL difference.
As well, the ability to run DX11 and its new features (primarily tessellation performance, which is extremely good with the 400 series) is a good selling point. His minimum FPS will also be significantly higher than his 275, and that in itself will provide a much more fluid gaming experience (trust me on this - i had a GTX 260 Core 216 (216 cores) and the difference between that and the 470 was unreal).
If he gets rid of his GTX 275 now, he can still get a rather good amount for it...if he waits to upgrade, he'll make a lot less for that 275 4-6 months from now.
So, OP...upgrade away, I've been in your shoes and I promise you that you won't be disappointed