I am feeling sorry for you man.
Now i do not have a fixed solution for you, but it would not hurt to check this :
http://www.subsim.com/radioroom/showthread.php?t=166943
I have severe trouble with SC and it could be that some options might work for you.
In my case SC is still not working, but there could be a chance that some suggestions work for you.
(Emulation, selecting a single core, just to name 2 things)
I have even read somewhere a suggestion to check some graphics settings. Try and mingle all your graphic card options, turn everything off.