What you should ask is: What did I reinstalled? and what I haven't yet? and what updates I am missing? and is there any drivers I missing or need to update? did I got latest pack installed?

but this is all just speculation on little data you give me >.>
need more things to know.

I had a friend that bought new video card and sayed he installed it properly, but his internet works really really slow, and whould load too long.
and what do you know what I find out when I came to him? he didn't even bother to insert CD that came with card and didn't installed drivers at all, and it was only his screen updating so slow LOL =P