The term "stock" in the chart refers to before we removed the heat sink/heat pipe assembly and re-mounted with the nylon washers. Like we said, it is an absolute no brainer as to what lowered temps almost a whole 10C on average under load with our overall overclocked settings of 477FSB and an increased vMCH voltage to 1.50v under load, just to add more heat to the testing. Idle temps lowered quite a bit and the drop off of the temperature from load was quite a bit steeper and far less gradual. So in the end, the stock heat pipe/heat sink assembly really isn't bad at all, heck, we would even go as far as saying it is pretty good. The only issue is that it appears that the assembly needs a little bit of help and added mounting pressure. Keep in mind, too much pressure and you will get into a warping issue with the PCB which we did encounter but we are willing to forgo that for much better MCH temperatures.
from :
http://www.hardwarecanucks.com/forum...review-16.html