AMD's Phenom X4 9950, 9350e and 9150e: Lower Prices, Voltage Tricks
 

When I started testing for today's review, I ran into the same issue again. I always start by benchmarking SYSMark first, since the suite takes forever to complete on a single CPU. As soon as I got my first results, I realized my problem was back. Determined to find the cause I tried everything...again. The one thing I didn't change however was the Cool'n'Quiet setting in the BIOS, but I did try it this time.

Cool 'n Quiet is the marketing name for AMD's on-the-fly clock speed/voltage adjustment. Depending on the software load on the CPU, AMD's Cool'n'Quiet will adjust the p-state of the CPU cores - which includes adjusting core voltage and clock speed. If you're running a processor intensive game or application, CnQ will make sure your CPU runs at full speed, but if you're just typing a text document it will underclock/undervolt the CPU.

http://www.anandtech.com/cpuchipsets...spx?i=3344&p=1