Overclocking greatly varies due to what hardware is being used and who is doing the overclocking. Always remember that no two pieces of hardware will perform the same, so our results will differ from what you might be able to get.
With stock BIOS settings, the Intel Core i7-975 Extreme Edition processor runs with a 133MHz bus speed (base clock) and an x25.0 multiplier that is used to reach the final core clock of 3.34GHz.
Since the Intel Core i7-975 Extreme Edition processor is an unclocked enthusiast part you can increase the multiplier and bus speed for better performance. By leaving the CPU Core Voltage at Auto and increasing the multiplier we were able to reach an insane 4.41GHz. Not bad for a system that was running a Thermalright Ultra-120 eXtreme 1366 RT (air cooling) heat sink. This is an overclock of 1069MHz, which is impressive for any processor.
To try out the overclock we fired up 3DMark06 and a number of other applications and found that the system was rock solid. With the Intel Core i7-975 Extreme processor running at 4.4Ghz we were able to put down some series numbers as the CPU score on 3DMark06 was found to be 7776, which is a new record for us here at Legit Reviews. The Intel Core i7-975 Extreme Edition processor scored 6107 at the default clock speed of 3.33GHz. This is an improvement of 27% in this benchmark.