I don't know what it is but flash just kills my pc (x4 955, 4gb ram, 6850). I have even tried a fresh install of my OS and flash still just kills it. Sometimes firefox will become painfully slow on flash sites. If I bring up a flash site while I am playing a game the game gets real choppy. The thing is I don't notice this at all on my two laptops (both older c2d laptops), and I don't know why the problem would persist through a reformat of the os?