Comment 150 for bug 967091

Interesting. Maybe the bug is related to the different VDPAU feature sets: http://http.download.nvidia.com/XFree86/Linux-x86/295.53/README/supportedchips.html
Quadro 2000 and your friend's GT 430 is feature set C, I am affected with GeForce GTS 250 (feature set A) and others seems to be affected with other feature set A GeForce desktop GPUs. On Adobe's bugtracker, there are users reporting the same bug with feature set B (and B1) GPUs. But there's a report by Adrian on GT 240M (feature set C) which breaks this theory; maybe we could link the bug to some particular GPU feature.

For the feature sets overview see http://http.download.nvidia.com/XFree86/Linux-x86/295.53/README/vdpausupport.html#vdpau-implementation-limits-decoder
There seems to be, however, no difference in terms of H.264 support. Maybe there's some particular, additional feature which allows Flash Player to use full video acceleration, therefore preventing this bug to show up.