Yo, It's FaTaL_GTR here,

I have this problem with Fallout New Vegas for the PC. I've done about one play through on my pc, however now whenever I start any play through or continuing one of my saved games all the NPC's glitch up. Now it doesn't stop game play however it does hinder combat greatly. The NPC's basically clip(float) into the floor, they also float in the air maybe about 20cm off the ground. Doc Mitchell even had his head spinning around. Also when they try to sit down they kind of like lay down on top of the chair. I will get pictures and possibly even a video of it soon. If anyone knows what I'm on about please comment and help me out.

~~Azzy