Performance problem with geforce 7900GT

[Tay Joshkin]

I hope this is the right question, sorry for the traffic and please don't feel bothered :-/

Just a few days ago I bought a GeForce7900GT powered board and although it performs great in games - it really is a looser when it comes down to "real" work.

Many KDE programs are extremly slow, GTK isn't better a lot however it seems GTK is running very slow overall and Qt based applications only if a lot of text is displayed. My LCD is running at 1600x1200.
I noticed that disabling cleartype helps a lot for Qt apps, GTK is still slow.

Any ideas what could be wrong?

Tay