Horrible rendering during multiplayer

[mr Hobo]

Hello all! I was one of the few that had no problems play GTA 4 on my computer. I can play on almost max with almost no lag what so ever. However, When I play multiplayer the rendering is messed up. Things are VERY VERY low texture and sometimes not even show up when I'm near them. It takes about five to ten seconds before things are rendered to a point where i can make out what they are. This makes it very difficult to play online.

Any ideas?

EDIT: this is for the PC version BTW