So thanks to rroonnaalldd, I was able to get my GTX 260 Core 216 and GTX 570 on Prime Grid crunching away. My only issue is the poor perceived performance of the GTX 260. A PPS (Sieve) 1.39 (cuda23) takes approximately 40 minutes on the GTX260 and just over 10 on the GTX 570. This sounds strange, because the GTX260 has 216 cores and the GTX570 has 480. While they are difference architectures, they are somewhat similar.
Does anyone else have a similar experience?
I forgot to add that the tasks were a bit different. One ended in a 0, the other in 1. Apparently the tasks ending in 1 take much longer? Is that correct?