Wow, someone seems to have asked about this in 2006 already and still don't have affinity settings?
On top of the basic affinity request, I would ask a special... I run BOINC tasks on all my machines and use process tamer to max out the GPU calculations... however, I discovered that if I set the affinity to a single core, I get much better performance!!!!
So I would need to automatically set affinity of each task to either Core 4 or Core 5 (for instance) since I have two GPU's in each system and at least 6 core processors running them all. (My fav is AMD 1100T's).
If one could set affinity according to which GPU is being used (one system will have 4 GPU's) then that would be nice!!!!