I own an ASUS K53TA. A few months back I noticed that my CPU was stuck at 800 MHz even at High Performance mode.
So I tried re-installing drivers
, re-install windows, run Prime-95 but nothing worked.
I sent the laptop for RMA and after struggling to figure out what to do for 2 months (LOL!) they replaced my CPU entirely.
I checked at the service center in cpu-z that the CPU was working as expected giving a clock of 1.4 GHz with occasional 2.3 GHz turbo boost. But the battery was dying so it went to hibernation automatically. After I recharged it to full battery, I booted into windows resume and the problem appeared once again.
But the CPU works fine in linux systems so I think the problem is with hibernation.
The GPU works fine so there is no problem with the power supply.
How can I reset the CPU???
P.S. Re-installing windows didn't work.