I think my system is underperforming, need help identifying the cause.

What multiplier and bus speed for the OC setting? What are the RAM settings?
By that score, I wouldn't say your system is underperforming. I'd say maybe it's even slightly above average. Your CPU holding back your scores due to it's low multiplier and difficulty to get past 430 - 440 fsb. If you can borrow a friend's e8400, that motherboard will easily run it to 4 Ghz (9 x 444 or 8 X 500) and you'll see your scores past 18K!

^+1 yeah, what he said.

Hey, thanks for the reply guys, that was quick!!

I originally left my memory timings at stock, and they were 5-5-5-18-2t with the ram voltage set to auto, which put it at 1.8V. To be honest, I didn't know what setting I should try to modify these timings too, so I just went with 5-5-5-15-2t and left the voltage on auto. A small change, but it was the first time I have ever adjusted timings before, so I was taking small steps needless to say. I looked up the specs of the XMS2 and Corsair stated that the sticks could be run at 4-4-4-12 @ 2.1V, so I went into the BIOS and for precautions I geared down the processor overclock to stock speeds and proceeded to apply the new said timings and voltage. Unfortunately, the system wouldn't boot at all, and it made me change everything back to stock in the BIOS before it would load Windows, so I was a little dissapointed there.

As for the multiplier and bus speeds. The q9300 has a 7.5 multiplier and runs at 1333mhz for the stock fsb. In my OC I didn't change the multiplier, I solely bumped the bus up to 1600 and put my voltage at 1.32 on the vcore. However, and this has always puzzled me by the way, when I view my cpu in cpu-z my multiplier is fluctuating between 7x and 6x, not 7.5. In the BIOS when I try to adjust the multiplier, it will only let me select 6 or 7, and I cannot enter a half number there. So am I losing that .5 multiplication? When I run 3dmark and submit my score, I see that it reads my mhz accurately @ 3000 or @ 2500 when stock, yet on the boot screen when I first turn my computer on it shows @ stock speeds it says 2333 instead of 2500... so any advice from here would be great, or just some explanations as to why this multiplier mix up is occuring.

I would also like to mention that as far as software goes I am running Vista 64-bit and all my drivers and BIOS have been updated.
I also had a friend suggest to me that my RAM and Vista are what's causing my system to not post such high scores. He has a q6600 with some ddr3 RAM(not sure what speed) and a GTX 260 card and he is posting 13.4k with no OC and 15.2k with an OC to 3.0. I know he has a newer graphics card than I, but unless I am mistaken the 9800GX2 still has more muscle than his particular card, albeit with outrageous heat and power consumption, lol. This dude also runs XP and has like 6 hard drives and says that is what's causing him to score nearly 2k higher than me.

Thanks for the help once again!!

I apologize, but I forgot to ask one more thing. I have read about the 1:1 FSB to RAM ratio, and unless I am doing the math wrong with an OC to 3.0Ghz using a 1600 mhz fsb and 800 mhz DDR2 that should be the correct ratio. I read that you are supposed to take the fsb and divide by 4, which yields 400mhz in my case, and to take the Ram frequency and divide by 2 since it has 2 channels, which also yields 400mhz here. In my OC i have left the ram unchanged on it's clock speed, because I once tried to do a linked OC and it resulted in instability. Should I leave those values alone? Thanks once more!

The RAm timings should be left to stock or auto until you can find a stable overclock speed for the CPU. I wanted to know if you overclocked the RAM to, say, 900 mhz?

If you enable EIST, you'll see your in CPUZ your multiplier working down or up depending on the load so that's normal. The fsb will be more of factor than the CPU frequency. For example, my e8400 at 8 x 500 gives about a 2% increase in 3dMark06 than 9 X 444. Both settings are 4 Ghz but the faster FSB feeds data to the CPU more efficiently.
Have you tried to overclock the GPU also by 10 percent of the core and memory speed? That will give you some gains too.

I have stability with the OC of the cpu so far, but one question, should i adjust the voltage to the RAM if i OC to 900mhz? I also hate to sound like a noob for the lack of a better term, but what is EIST? I will try to OC my GPU by 10% in the meantime.

BTW, what should I use to OC my GPU with, what's the recommended software for a GX2?

I have

Q6600 @3.6ghz
P35 mobo
Geforce 8800GTS 512 EVGA
4 gig ram.

16.1k highest oc' thats with max gts 512 oc and q6600 @ 3.6ghz so i think its very decent score.

rivatuner, or atitool. Both are recommended programs.

Ok, i bumped the RAM up to 900mhz and for precautionary stability I increased the voltage from 1.85v stock to 1.9v. I downloaded Memtest and ran it for 30mins with no problems.

Concerning Rivatuner... I once had the program at some point last year installed, and I remember seeing and being able to OC my GPU, yet upon redownloading and reinstalling it, I am unable to see where this option is now. Perhaps I am just missing it, can anyone point me in the right direction here?

EIST is your BIOS setting in CPU configuration. It makes your CPU multiplier go up or down depending on load in order to save power.

Google it.