Computer is jittery when playing HL2, CSS

[Xecuter]

well, to start off, my computer is comprised of

Barton 2500+
ASUS A7N8X-E Deluxe 2.0
1 GB of Corsair XMS 400MHZ
Radeon 9700 PRO

It seems as if the format somehow adversely affected my computer, as In counter strike 1 i get around 50fps, when before I got 100.
When playing counter strike source or HL2, it is very jittery and laggy, can range from 20 FPS to 100FPS.

The settings in the game are High, with no AA and Trilinear filtering, nothing super demanding.

I have upgraded to the latest drivers from ATI.

I dont know what is causing it! Help please.

Thanks
-Xecuter

 

[Sforsyth]

coould be your onboard sound?

 

[Xecuter]

actually, that brings up another thing, in CSS whenever I fired a gun it would play the SFX twice.
could you elaborate on what you mean?
thanks
-xecuter

 

[Sforsyth]

I have a nForce 2 MOBO XP 3200 1 GB Ram and 9600 Pro and I had bad stutering in CS:S and BF2 I put in a PCI sound card and it stopped.

 

[Xecuter]

it worked before however...

 

[Sforsyth]

have you tried the Video Stress test? or try turning your sound quility to low.

 

[Sforsyth]

are you using Sympatico High speed by any chance thats what I have and it makes my games stutter to?

 

[Mogadon]

What about the nforce 2 drivers, you got the latest one's of those? Latest version of DirectX? Windows updates? etc ...

If it all worked before and all you did was to reformat it is a software issue.

I know it sounds stupid but have you tried using the older video drivers you were using before the format.