S!
I had no problems with the 580GTX with IL-2. But the 460GTX has received quite a lot of flak on forums due various issues. One remedy has been to disable HPET(High Precision Event Table) in BIOS of your mobo. Also try putting Multithread support OFF in NV Control Panel and see if it helps.
I get stutters with AMD 6970HD so not any better here either
But strangely only at certain angle! Oh well, gotta live with it
