Core 2 Extreme QX9650 Review

Overclocking

This CPU has an outstanding overclocking capability. Since we got an engineering sample, it had its clock multiplier unlocked, so we were able to increase its clock multiplier to x10 for a 3.3 GHz CPU, working just fine. The program that was most benefited by this internal clock increase was Cinebench 10, where we saw an 11% performance increase.

It was also really easy to increase this CPU external clock rate (FSB) up to 410 MHz (1,640 MHz QDR), but we achieved stability (i.e., we could run PCMark Vantage without crashing) only at 397 MHz (1,588 MHz), which made our CPU to run at 3.57 GHz internally keeping its default x9 clock multiplier. At this configuration we saw an 18.42% performance increase on Cinebench 10. Keep in mind that this program is the one that gets most benefit from internal clock rate increase, i.e other programs achieved lower performance gains.

This basically means that you can practically “transform” this CPU into a 1,600 MHz FSB part, which is the next external clock rate for Intel processors.