Originally Posted by bromzue
Its not a big difference, somewhere around 3-6% depending on the game. I would stick with what you have as the 192 shader 260's seem to overclock higher than the Core 216's.
My 192shader GTX 260 does 760core 1534shader and 2500mem. My best friend just purchased a EVGA standerd clocked 192shader 260 and his hits the exact same speeds.
You also need to get that CPU overclocked as high as you can get it while remaining stable because your CPU will be a little bit of a bottlneck for a 260.
I'd say that CPU will be a little more than a "bit" of a bottleneck for the 260.
Heck, both my old 185 and FX-60 weren't enough for a single 640MB 8800GTS back when I had the rig.