The key to a stable Quad overclock with minimal Vcore is to have some decent volts on the FSB, when i had my Q6600 at anything over 3.6Ghz i had FSB volts as +0.15 i think it was just to be sure of stability(it was folding). Also if you are on X38 chipset please be aware that X38 is very heat...
80 degrees should be the max it ever gets, i really dont like seeing chips at those temps! If this is going to be a 24/7 overclock then max temps should be 70 degrees for your card - if its just for benching then go get the desk fan off your sister and direct it on the card for a while :)
Dont even bother with DDR2, i have seen 1 in a 100000 actually work, and its never ever stable. DDR3 though is a different story so if you wait a while you can try that :)
Akubane has advised you well, if you want to go with water cooling then you must be prepared to spend a fair amount of money on it. There is no sense in going with a cheap water cooling kit, you may as well go with high end air-cooling...
Talking to one of your great members nitestick and he said something about these forums so i thought i would post my results here for you all to view, ive copied my post from my home forums :) enjoy!
Got the QX9650 last night...
Came in a nice big box and had some nice info on the outside...