@xonar:
SETI uses only CPU. GPU folding is only supported (by time of writing) using Nvidias card (CUDA). I've been testing shutting SETI and it has no effect on mining.

I've looked some of those cards and some of them can be bought on my local computer store. What these means in front of card model: HD, EAH and AX (tried search but didn't find answer i was looking)

@teflone:
How i know that? Does it say in box? And maybe stupid question, whats difference in those types?