You might be better off selling them both and getting a 460GTX. But you have time for that. I would surely start off with the 260 though. The thing to look for is low minimun fps. If that occurs you will need a stronger card to keep up with your 480's. I ahve been trying to do some benchmarks on xfired 5870 with physx but will have to wait untill my kids are back in school. I will be using a 9600GT, 9800GTX+, and a 460GTX for physx processing.....Hopefully by next weekend.