Is that i5 a quad core ? If soo, your doing a sidegrade more then a upgrade.
You have a nice CPU, save your money for VC possibly in the future like a ATI 7970
Oh but I just noticed your @ 2.6Ghz which is no good, lol you need to OC the CPU you have now to at least 3.8Ghz ......... Games take advantage of cores but I can tell you ,, on my Rig ,,,,, BF3 takes up avg 60 percent of my total CPU power as do all games. So your CPU is fine for gaming so long its a quad core ... If soo, that i5 to i7 is a sidegrade and pointless. You wanna see a difference, do a video card upgrade which you dont need to do as of right now, the 5850 is fine,,,,, for now,,,, What res you play your games @ ? If not 1080p ,, but a lower res then that 5850 should server you well for another couple years... thx gl