My imac has become so slow it is unbearable. It has new memory and fresh install of lion and is still really slow. The only other thing i can think of at this point is a HD issue. I have done a hardware test but it said everything is fine. So what and where should I get a HD from? It has a 160, and I was thinking of maybe bumping up to a 320? Thanks for the help. It is the white, core 2 duo model.