The old 260s don't work on GPUGrid but the newer ones do.
I'm too lazy to look up the exact shader count for each but I think the old is 296 and the newer 216?

A lot of the GPU usage and overall runtime depends on the WU type. There are some that run fairly fast and hot (KASHIF) and most of the others run slower with lower utilization. Then there are the WU that say *long* in their name which can take a VERY LONG time to complete. Please make sure you are comparing like WU types and even then there is some variation in runtimes.

I really appreciate the dedication and detail you are brining to the table ... looks like I may need to go in for another *testing* phase ... upping priority with eFMer and now DEP reg keys ... nice I typically test with the same exact WU so I can better compare resuts. I do take a hit on points for a week or so but I think it is worth it in the long run.

p.s. WinXP is MUCH more efficient than Vista/ Win7 ... between 20-40% faster runtimes easy