Issues with my pc PLEASE HELP!

hello all,
I recently been finding that my gaming rig isn't up to par on handeling recent games that well. To start off heres my basic specs:
A7N8X Delux v2.0
AMD +2500 @ 2.1
Mushkin 1G pc3200 black BH-5
Ati 9700 Pro agp
1x 200 gig WD
1x 40 gig Maxtor

I've been playing HL2 for acouple days now and iam running it at 1204x768 with all details on an AAx2,x4. It seems to run "alright" but i believe i should be gettin superb performance with these settings. I also get lots of slow downs when playing CS:S with these same settings. I video stress tested it and my average fps is 59.6 I recently formated my comp and put all recent drivers up to date, so i have no clue whats causeing the slow down. I never have anythign run int he backround so thats not the case. I also see lots of slow downs with doom3 and a few other games. Can anyone help determine whats bottlenecking my comp?? It should be running every recent game up to par! PLZ HELP!!!

Do you overclock, is your system set to slow down at high speeds, do you have good cooling?
What kind of video-card do you have? I don't see it in there. Also, what are your 3D mark 01 and 03 scores?
Welcome to the forum btw

i got a 9700 pro, yes i overclocked my cpu to 2.1 gigs, and what do you mean is my system set to slow down at high speeds? yes i have good coolings

What kind of cooling are we talking about, and is your video-card overclocked?
Often systems are set to slow down at high tempetatures, so service isn't interuprted, just slowed.
If you could post your GPU/CPU/System temps, that would help.

nothing runs to hot. My cpu at the hottest can go up to about 57c or so and my mobo never runs to hot or the video card. I already ruled out cooling as the problem

Check how windows is using the paging file. Might be transfering the RAM load over to it for some reason.
Also try downloading the drivers again, every once-in-awhile you get bad download..

Could you please post CPUz screenshots? My initial guess is a non-defragmented HDD is causing your slow downs. You absolutely must defragment your HDD atleast twice a month. HL2 and Doom 3 are very demanding games and I don't think your video card/CPU combo (more so CPU) can handle the full blown features (everything at absolute max). Also, maybe small errors due to your OC may affect your gaming ability.
You need a stable system first to game seamlessly. Give us more info and I'm sure somebody will help you out.

PS* Does this slowdown occur when you don't game? And do you see any artifacts in your games?