I don't know why everyone is holding onto the idea that Prescotts don't OC well. On the average Prescotts seem to oc just as high, if not higher, and more frequently than Northwoods. I beleive this is mainly because of the fact that the Pressy is the successor to the northwood and since Intel plans on coming out with higher mhz prescotts in the next few months while the northwoods are maxxing out at 3.4(to my knowledge) they prescotts are going to have more overhead. If you are going to be watercooling and are serious about overclocking then I would go with a prescott because the L2 cache increase gives a good boost to your memory bandwidth, which is always nice. So if on water and overclocking, I'd go with a prescotts, and if your not overclocking, or just overclocking on air, I would go with a northwood. And for phase change, I would go with a northwood, because unless you regass a phase change unit and mod it a prescott won't really get into a nice beneficial temp range.