Here it goes.
 
I had:
 
Asus A8N-SLI Premium
AMD64 4000+ 1MB L2 clocked @ 2.6
512x4 OCZ DDR400
7800GTx2 SLI 450/1050
250GB SATA
Ultra 500W PSU
Windows XP SP2
 
That was my old build. On my old build I played TF2 in 1024x768 everything on low, with 2x AA and Trilinear filtering.
I would get about 80-150 FPS @ spawn and when I was in the middle of bigger fights it'd bounce between 35-55
 
I just build this new PC:
 
Asus M2N32-SLI Premium
AMD64 X2 5000+ Black Edition 512x2 L2 clocked @ 3.1ghz (34C Idle 45C Load)
1024x2 OCZ DDR800 5-5-5-18
8800GT 512 DDR3 660 core clock (this is the MSI 8800gt that came with an aftermarket Zalman-like cooler idle temps are 42 load of 55-60)
250GB Sata
Thermaltake Tough Power 650W PSU
Windows XP SP2
 
 
With this new build no matter what setting I put TF2 on I get about 100+ constant at/near the spawn and when in fights I get 25-55 FPS...weather I have 8xAA and 8xAF with everything on high w/ motion blur etc, or if I have everything on low in 800x600, I get the same bad results in all fights, just crappy FPS.
 
I ran 3dmark06 and I got a score of 6077...this is FAR too low for. What could be the problem with my computer?
 
Also I can barley play COD4 Bioshock HL2:epi1-2
 
In the above single player games, if i turn everything and or most things up, I get 35-55 FPS.  
 
What in the F is going on.
 
 
 

i would guess from the low 3dmark that your gpu is faulty, or the psu is not supplying enough power to the gpu bc it is faulty.

well, when i oc my e2180 from 2ghz to 3ghz i go from 7400 to 11200 in 3dmark, so I suppose you moight be cpu limited? ><

Did you do a reinstall of your system, or transplant the OLD HD in the new hardware. If you transplanted without a clean install that is the problem.

the 3dmark score is very low, how does it compare to other cpus at that range? does it score low in all 3 test, or just one?

That is low, roadrunner makes a good point. Something is amiss that cpu and video card should obliterate TF2. If you haven't reinstalled windows when you upgraded you might try that, if that doesn't help then I would try another PSU. That one should have enough power but it sounds like it might be faulty.

Same size HD...is it in fact the same HD with the old install still on it?
Your new GFX card should be dusting the old one and 3Dmark06 should be 11-12K

I went from a 4200+ to a 6000+ without a clean reinstall and the performance increased when I did a reinstall of the OS. Also check performance at stock settings incase the PSU isn't supplying enough power for the OC. Also try your old psu and see if that works.

Thanks for the fast replies.
 
When I upgraded I did do a full format and reinstall of windows. I doubt my Ultra 500W PSU will work with my 8800GT.
When I first built the PC I didn't have the 8800GT, I had my 7800GT x2 SLI, and my PC kept crashing as soon as I opened games. When I swapped out my Ultra 500W for my Thermaltake 650W with 4 12V rails, no more problems with the  7800GT SLI....though i suppose 1 8800GT takes less juice than 2 7800GT.
 
I just got done formatting and install windows >
 
I'm in the middle of downloading TF2, I'll see how it performs when it's done, and I'll also run 3dmark06.
 
As for the PSU not supplying enough power due to OC-ing, OC-ed or not, my PC had the same symptoms either way.
 
I suppose I could have a problem with my Mobo/Ram/or CPU, if this doesn't work I'll rebuild my amd4000 system and see how she does with an 8800GT. Im going to swap out my DDR2 800 for DDR400 for 1 run to see if my ram could be causing problems also.

I just ran 3dmark06 after a full format and reinstall of window.
 
scored 6272, i Never broke 45FPS on any test, and spent most of my time starring at 15-18fps.
 
what in the hell.
 
im rebuilding my old system and will see how a single core amd 4000 works with a 8800gt

Can u give us the break down of 3dmark06 score. It will help determine bad GPU or CPU.
 
Can you confirm that both cores are showing up? That could be the problem as well.
 
I'm not an AMD man but dont you have to download something to get both cores going sometimes?

@roadrunner, you mean the dual core optimiser about the psu try the 500 mate I had an 8800gts and an 6000 @ 3.2ghz running on a 450 watt, then we can rule out the psu if performance is the same. Just keep ruling out components until you can single out the problem.

Whatever it is called. Like I said, not a AMD fan. I like Intel plug and play.

Well I did a little test there on 3dmark and I didn't see a performance increase with it only a minor drop 3-4 marks so imo is application dependant, that said I only did a quick test in 3dmark. I think its his psu, if not then he needs to reinstall vista with the proper drivers for the cpu etc since he went from a single core to dual.

Out of curiosity is the bios updated on your motherboard? I only ask because when I built the missus new beastie I put a 5k Black in it and it ran like an absolute dog until I found out the bios didnt support the G2 stepping. Once I got that cleared up there was much vroomage to be had.