To test power usage I ran the system at idle for 20 minutes and took the wattage using an wallplug wattage meter. For load results I ran 3Dmark11 for a for 20 minutes and did the same. While CPU, motherboard and RAM were different in each test setup, the GPU was identical.
Despite already being quite a workhorse, the Sandybridge 2500k is a strong overclocker too. Pushing it’s performance up is a little different to CPUs of the past, as it’s main clock, while alterable, is linked in with many other controllers. This results in poor system stability after only a few MHZ. While there are methods – including Intel’s own TurboBoost – that allow for some basic overclocking, those with a K based CPU are in luck as their multiplayer is relatively unlocked. This allows for very simple CPU clock altering as some impressive OC results.
After just a short time playing around I was able to push the 2500K from its stock frequency of 3.3GHZ to a much more impressive 4.3GHZ. This was all using the Arctic Cooling Freezer Pro 7 Rev 2.0, hardly the world’s beefiest CPU cooler. With improved cooling it seems likely that I could achieve even higher overclocks with this chip, but considering this PC’s setup I opted not to push it further. Even after only a few minutes of 100% I was already hitting mid 70s on every core which is starting to head in a dangerous direction.