Random stutter in MP and SP of COD4

I always get a random stutter/lagspike during both the SP and MP of COD4 about every 3-4 min or so. I basically lag for about 2 seconds and can't tell what in the world is going on. It's not my internet because my other games don't do this, and I've tried different servers. My graphics card is a 7800gt but I'm only running everything on pretty much medium settings, and I've tried lowering them too. Anyway, any ideas why this is happening?Random stutter in MP and SP of COD4
hey i have the exakt same problem. I have the same card.

make up brushes