8800GT strangely low 3DMark score ...

Hi I've just bought a 8800gt (asus branded) and I'm getting very dissapointing 3DMark 06 results, and am hoping someone could give me some possible causes. I get a bit over 3000 for both shader 2.0 and 3.0 which im fairly certain is very low for this card. My CPU score is around 1600 which is about right. In total I get around 7500. My rig is as follows:

Athlon X2 3800 socket 939 (@2.4GHz)
1GB DDR3200
Asus 8800GT (@stock)
Foxconn NF4SK8AA (nforce 4 chipset)
Windows Vista Ultimate

Using nvidia forceware 169.02
When I run 3DMark 06 it reports that there is no systems similar to mine to do a comparison which seems strange as I hardly have very high end or niche components...
Worth noting is that I only have a generic 400W power supply, could this be the cause of the lack of performance? The system is very stable so im not sure it is. Could it be my rather out-dated motherboard and ram, although my CPU score is what I would expect.

Any suggestions appreciated. (Apologies if this is in the wrong subsection, I'm new!)

If you want a higher 3D score switch to XP.

The 3DMark06 scores do vary and are influenced by the processer as well as the GPU. Your score is very low, but your CPU is the bottleneck here. Crysis runs much better on duel cores, in "Task Manager both my cores were above 60%. On my old P4 3.0GHz, 7800GTX 256MB, 2GB of RAM got in 3DMark06 5438 score. Always buy a quality PSU from brand names like Enermax, Antec, OCZ, PC & Power Cooling and Corsair.

Like others have said,
1GB of ram with vista is not enough so either swtich to XP or buy more ram
also your processor is a big bottleneck.

Hey thanks to all for the replys! Are the 3DMark shader scores independant of the CPU? I know the overall score includes the CPU but I thought for the shader scores only the GPU counted?

AMD cpu is the reason for lower score. You need more ram too (faster if possible)
I have an AM2 X2 5000
cpu score 1876
3Dmark06 score 9169

Change your PSU, 400W is ok, but generic ones are somehow dangerous for good video cards. A friend with a 1950pro used for some months a generic PSU, then it died and the video card still has some issues sometimes (random restart). Now he has a better PSU, but it was too late.

Like most people said it might be the CPU or RAM that causes the bottleneck.
There might be another reason though. I have a friend that have a Nvidia 6600GT with defective thermal sensors. The thermal sensor always register a temperature of 150C. As a result the driver automatically underclock the GPU and the performance was reduced by more than 50% (I remember him running FEAR performance analysis at that time and only get 30FPS at 1024x768 with that defective card). He choses to return the card to the store and get a new one.
Check your card temperature, maybe that's the problem.

My mobo is an nForce 410/430

"Am i the only one who thinks his problem is the motherboard? nForce 4?

Can't possibly keep up wiht the 8800GT's speed."

AMD cpu like I said

Yea but switching to XP will kill all dx10 or dx10.1 effects .... can't be had in XP !