Test System

Initial Setup

The initial setup proved simple and easy, with the BIOS automatically setting a default speed of 3.5 GHz under Turbo mode, and defaulting the memory to JEDEC standard 1333 MHz CAS 9. We ran several rounds of Memtest x86+ to verify stability, and then installed Windows 7 64-bit. We then enabled the 2133 MHz XMP profile for our Corsair memory, and ran Memtest x86+ again. While Memtest x86+ proved to pass with flying colours, we found that when in Windows, we encountered some stability issues, which were remedied by increasing memory controller voltage from a default 1.05 V to 1.124 V, and unlike the last product we looked at, we also had to increase the DIMM voltage to 1.7 V, considerably higher than we were expecting. After several hours of stability testing with various programs over the course of two days, we found sweet spots for both CPU and memory speeds when overclocked, and then reset the BIOS to default speeds and JEDEC timings, in preparation to begin our usage and performance testing.

PWM Power Consumption

Since one of our first tasks was to truly verify system stability, while doing so, we measure CPU power consumption. We isolate the power coming through the 8-pin ATX connector using an in-line meter that provides voltage and current readings, as well as total wattage passed through it. While this may not prove to isolate the CPU power draw in all instances, it does serve as a good indicator of board efficiency and effective VRM design.


The ASUS P8P67 PRO really surprised us on the power consumption front. We noticed only two watts consumed by the VRM at idle, while loaded that number jumped up to 73 watts, proving to be 5W less than the boards we previously tested. We enabled the EPU switch to see what further power savings could be had, and noticed a drop of another 6 watts at load, although we did have to tweak the bios a bit to get the clocks higher than 1600 MHz on the CPU for an adequate compare, as the EPU setting was set to "Maximum Power Savings". Does that power savings exact a performance penalty? Read on to find out.