Nowadays, chip manufacturers design a wide range of protection mechanisms into their components, preventing careless combinations of settings or a lopsided heat sink from doing harm. Eventually, your CPU or GPU might destabilize or even fail. And if you run your overclocked build at too high a temperature, a phenomenon called electromigration can degrade your chip’s circuitry at a rapid pace. When temperatures rise too high, silicon can throttle back its clock speeds to preserve itself, harming performance. Is it possible to enable EC support also for the CPU fan? Its speed can be read from EC offsets 0x93 and 0x94 (register 147 and 148), and the method is the same as the one for the GPU fan.Heat is the worst enemy of PC hardware. The 'problem' appears when my CPU fan goes at maximum speed (that is supposed to be about 4100 rpm), HWiNFO reports 25500 rpm, that is obviously a wrong value.

Regarding the CPU fan, it seems that HWiNFO does not use EC support for it, but it reports this speed reading from ACPI objects, and does not report the actual exact CPU speed, but fixed values (2200, 2300, 2400, etc). I calculate myself the speed value using this method Fan Control on Asus Prime UX31/UX31A/UX32A/UX32VD. I use Notebook Fan Control to control both fans.Ībout the GPU fan speed, HWiNFO uses EC support and it works well, reporting the exact actual speed reading from EC offsets 0x95 and 0x96 (register 149 and 150). I have an Asus ROG G751JY, using HWiNFO64 v5.36-2960, that shows me both CPU fan speed and GPU fan speed. I use HWiNFO since years without a problem.

First of all, thank you for the excellent work Martin.

Asus rog cpu fan control