There are quite a few different ways to overclock on the P9X79 Pro. First let’s start with the easiest, Auto Tuning. Open up the AI Suite II software and go into the Auto Tuning section. Here you can select fast or extreme.
I decided to pick fast and the system restarted and gave me a 29% overclock by moving the BCLK to 126.4 and the frequency to 37. Giving us a speed of 4.675GHz, not bad at all!
Now if you do want to overclock your system within Windows you are able to do that with the TurboV EVO software. You can change the CPU ratio, CPU strap, and voltages all within this software. When you change the settings and hit apply you do not have to restart the system, which is nice.
Of course I wanted to do my overclocking in the BIOS. We are using an Intel Core i7-3820 processor so the max multiplier we can set is 43. So I set it to that and kept the BLCK at 100. With this setting it put my system at 4.3GHz.
This is a good overclock, but I knew I could do better! Sandy Bridge-E processors have what’s called a CPU Strap. It is used as a master multiplier for both the processor and memory. It can be used as 100, 125, 166 and 250. To give you an example if you are using the base Clock Ratio of 36 and have your memory set at DDR3-1600 when you change the Gear Ratio from 1.00x to 1.25x your CPU Frequency will jump to 4.5GHz from 3.6GHz and memory to DDR3-2000. So I changed my CPU Strap to 125 and started to move my CPU Ratio up until the system would not boot. At 5GHz (40x CPU Ratio) the system would not boot. So I moved down to 39 (4.875GHz). The system booted, but failed our stability test. So I moved down again to 38 (4.750GHz). This proved to be a stable overclock. And not a bad one either a 1.150GHz overclock over our stock speed!