AMD processor reduced to 0.38 GHz performance
AMD processor reduced to 0.38 GHz performance
I didn’t aim to bring back an old discussion, but I wanted to share my thoughts after six months on what functioned and what didn’t. I couldn’t get past any CPU temperature monitoring tools using external programs, so I wouldn’t recommend that path for others facing the same problem. One alternative I discovered was accessing the UEFI settings and turning the "Fan Always On" option on. It helped for about five months before the fan stopped working properly again.
My final approach started with checking the laptop’s diagnostics using HP’s service guide. It turned out the CPU fan was the culprit. After buying a replacement part from AliExpress (part number M45465-001), I installed it and everything operated normally. I ran stress tests, and even the Fan Control settings in HP Command Center remained functional.
After extensive research, I identified two possible causes: the third fan wire’s tachometer was giving incorrect speed readings, leading to faulty PWM commands, and a failed transistor (FET) between the controller and motor coils, causing misinterpretation of pulses from the fourth wire. This explained why the "Always On" setting worked for so long—it likely ignored both signals and only used the first two wires.
The fan’s erratic behavior sometimes started briefly, slowed down, halted, then spun backward. Ultimately, the simplest fix was replacing the fan entirely rather than digging into complex diagnostics. I also learned that HP might have a backup mode after a 90-boot error that automatically reduced CPU speed to 0.38GHz.
I used iFixit tweezers to repair the rubber feet and adhesive, which now last several uses. The stock feet stay intact, and they’re still holding well. My airflow remains decent with them, though placement isn’t ideal. HP also offers semi-manual fan control via Command Center, but it doesn’t let you adjust speed as finely as third-party tools like Fan Control.