MW2 - unplayable performance :/

[Ziggy]

I've just installed MW2 and I've encountered a bug. On the first proper level the game runs perfectly for 5 seconds, then completely freezes for ~8 secs, runs again then freezes again ad infinitum, rendering it unplayable. At first I thought it was just loading textures etc. but it never stops.

The training mission ran flawlessly and the first level has a good framerate when it's actually working. I dunno what's going on.

My PC's no monster but it should be better than that:

Core 2 Duo @ 3.6GHz
Radeon 4870 (latest drivers)
4GB RAM
Vista 64 bit

I've tried restarting and defragging but it did nothing. Any ideas?

 

[Ziggy]

Yep everything is up to date, and the CPU's been at that speed for over 2 years, rock solid in everything.

 

[Ziggy]

Dropped the textures down a notch and it's working perfectly, wasn't the overlock.

I shouldn't have to reduce the graphics just because they haven't made the game properly. >:|

Don't think much of the campaign so far tbh.