Help me fix my Framerate problem, Please!

[BEn_2600+]

Specs:
Intel [email protected]
Asus Maximus Formula X38
4GB Crucial balistix
HD3870
X-Fi Xtreme music
22" Screen
Windows XP x64

Basically, in TF2 COD4 COD2(about the only games i have on my system) I get bad FPS, but sometimes its really bad, COD4 1680x1050 4xAA down in the low 20s. basically the X1900XT that it replaced performed better.

Things i've tried:

Catalyst 8.9, 8.7, 8.6, 8.8, 7.11, 7.12 (7.11 fixed the problem but the it randomly crept back)
installed Vista x64
Re-installed XP x64
Re-seated GFX card
Force AA in CCC and set in-game AA to 0
Overclock GPU core ranging from 800MHz to 900MHz
Overclock system to 3.0GHz (430MHz FSB)
Also had the same problem in a P35 (Asus P5K-E)

Since i installed the Graphics Card the whole system has changed i get lag when scrolling a web page fast (although not major) COD4 freezes for a second or so when you first enter a server.

I haven't got a clue what it could be but the Cards going in the garden if it carries on..

Please help

 

[Deimos]

Sounds like a driver problem, uninstall the current drivers with a driver cleaner and download the latest ones then install those. I had the same issues with general web browsing and games with a dodgy driver, not that card though so could be something different.

I read you tried different drivers....but i'm sure it must be a driver issue

 

[BEn_2600+]

uninstalled Drivers, Ran driver cleaner and CCleaner, re started installed 8.9 drivers...Same problem

 

[BEn_2600+]

Strangely, i have set COD4 Affinity to only use 1 core and FPS seems sooo much better, it certainly dosen't feel laggy and frame rate only drops to high 50's at spawn. i thought COD4 was multi-threaded