Try the "real" nvidia driver. If you haven't set up any third party repos yet then
rpm -ivh http://rpm.livna.org/livna-release-8.rpm
yum install kmod-nvidia -y
shutdown -r now
And see if that helps. But now that you have Livna installed try to stay away form other third party repos, Livna should have most stuff anyways, multimedia players, codecs, etc.
BTW why no compiz? on your setup you wouldn't even notice it was running, except for the eye candy.
If you change your mind, leigh has a repo setup for fusion which makes it a breeze.