Getting white lines in Doom 3

[blix]

I'm getting white lines across the bottom of the screen at all times. It doesn't occur in the menu, only in-game.

Here's a pic:

I'm on an ATI 4870 with the latest drivers.

I can't find a solution to this on the net. Anyone got any ideas?

 

[AWPC]

Works perfect for me on a 4870 with cats 8.9. What level of AA you using as some methods cause this to happen on certain games also if your on vista do you have the sidebar disabled as that can cause it as well.

 

[blix]

It was indeed the anti-aliasing. Thanks a lot.

 

[snowdog]

AA often displays lines on the left side and bottom for me, especially when the screen goes black it's noticeable in about 50% of all games... Stopped caring about it myself as I prefer AA than no AA .