I know this is a bug since fallout 3, but i'm not sure it's very common since I've scoured google and these forums before deciding to post about to see if there's a fix or if anyone has more info about it. If (and only if) I have a weapon equipped and open the pip-boy, sometimes it will be too high on the screen and I can only see the bottom half of it. It happens incredibly often with most rifle and two handed weapons, rarely with one handed weapons, and never when I have my weapon holstered. A quick fix is to holster my weapon then open my pipboy, or if I change weapons in the pip-boy while it's off center, it will usually re-center itself. Sometimes I can predict when it will happen as if I have a rifle equipped and stop moving, the graphic for the rifle will jerk up a few pixels in my view. It happens enough to be incredibly annoying, especially since usually the times you really need to get into the pipboy is to use a stimpack in the heat of battle when you can't afford to leave the screen, holster your weapon, and open it back up. Again, I know this is an old bug, but there's not a lot of info on it, so any info from previous threads or new info would be greatly appreciated.

Windows 7 x64
nvidia GTS 250 w/260.99 drivers

Edit: I'm pretty sure this bug is related to the 'gun +arms falling down the screen' bug, since it has the same effect on the pipboy.

I have this same problem but it is even worse since I'm only using one handed weapons. It also gets stuck like that until I quit the game.