Hi, I've got RIVA TNT and it worked well with XFree86 4.3.0. As of Fedora Core 2 Test 3 it stsrts nicely with KDE and works until I actually run somethig. It locks my computer even if I want to run desktop config. I had exactly same story under NetBSD with XFree86 4.4.0 where it locked my PC when I tried to to do ls -lR / which was quite fast output. So I guess rhat the nv driver for this card is broken and it's not kernel-2.6 related. But if you have any solution (better driver) please post it.
Thanks. Janusz.