I was having a problem where, when outside and underneath things that should cast shadows, I would get flashes of light and thin lines shooting across the screen. Wasn't good.
First I tried re-installing Skyrim, which did nothing, then I updated my video drivers. Now it is much worse. Some polys are missing, some are exploding all over the place. It's madness.

I was going to post an image here but it says I'm not allowed. That's very unhelpful.
I really don't know if I can properly describe this, but there are planes of stretched out textures all over the place, and NPCs have black holes all over them.

Device Manager says I have an "ATI Radeon 3100"
Any advice?