Dude, running 4 quad-core procs. That's just sick lol. But IMO, updating the chipset or other drivers generally doesn't make a HUGE difference, unless there was a really nasty bug in them to begin with. You have a good video card, it's older now, but still remains one of the most loved cards of all time.
It might help to upgrade your memory. Memory is so cheap now, it's almost silly to not have at least 4GB. I recently upgraded my PC and bought 4GB of DDR3 memory, and it was under $100. Also, a point about the memory, if you have dual channel memory (which you totally should), make sure that you have the chips in the right slots for them to operate that way. If you put dual channel memory in the wrong order, you're essentially cutting your performance in half. The "right order" will depend on what motherboard you have, as there is no one right way to do it. It all depends on your mobo.
Also, you said you're running a 360GB RAID hard drive. Does this mean that you're running 2 hard drives with a mirror RAID, or that you're running 3+ hard drives with striping on that total up to 360GB? You can't run a single drive in RAID to my knowledge. And even if you could, it would be pointless.
Another thing to think about is: how long has it been since you've reinstalled Windows? If it's been a long time, you might wanna go that route. If you're really trying not to spend any money, you can also check out the web to find guides that'll tell you how to tweak you're rig. There's tons of them out there. I've used them and they work well. Go through SERVICES.MSC and disable any services you don't need (trust me, there's a lot).
Sorry for the late reply, my hard drive crashed last week and I literally got my PC working again like an hour ago
