[gampamu]

From what I have seen, the frequency of the CPU effect on the CPU temperature only to a small degree, compared to the effects of the vcore.

I have been playing around with a QX9600 for a couple of days on my EP45-UD3P, a board very similar to yours except it uses DDR2's. Perhaps we can trade some notes.

I am finding these QX's run quite hot. 10-15 degrees hotter than my previous chip, the Q6600, at the same vcores! Not much overclocking would be advisable using the stock cooler. Getting the Ximgmatek S1283 was a good choice. It performs on par with some of the best air-coolers such as the TRUE (which I have) at about half the cost.