I have an AMD 9950 BLK ED processor, it was out of the box 2.6 ghz. I installed the supplied heatsink, and oced to 3.0ghz, with little temp. difference, but also i agree with other answers, 350w is just not enough, this processor run 140w just at factory clock, i would recommend at least 500w. And not sure what you would want to overclock for, this processor can easily keep up with an hd 2600, if you had a pair of them then maybe overclock. My system, has 2 9800 gt 1GB in SLI, and i am back down to factory clock on my processor, and it seems to keep up with the cards no problem. It just depends on what you are using your computer for. I have a friend that has the 9950 also, liquid cooled to 3.8 ghz, he said thats the max he can go without crashes, so this processor is factory clocked to about 2/3s its potenial, but just remember keep it cool, and it wants lots of power! also make sure if you do upgrade psu, get one with dual 12v rails!