M15 R5 CPU clock speed goes to 1.xx GHz when gaming, base clock speed is 3.2GHz

Does the system recognize the AC adapter (F2 at powerup to check) and what is the condition of the battery (run a battery report -- from a command prompt with admin privilege, type 

powercfg /batteryreport

What are the current and design capacity figures for the battery?

Another easy thing to check is the power plan. Are you set to Performance or Balanced?

Settings > System > Power & battery > Power Mode

@ejn63​ Let me reply with screenshot, so it can be clear

and the powercfg

or should i send the report instead?

@DELL-Daniel V​ Sadly, i do not have it

@DELL-Daniel V​

Got the high performance already using some script in CMD Terminal.
But still, no good 

If you haven't run a diagnostic to verify the fans are working, that would be a good idea.

The system uses something called Hybrid Power, which taps the battery when the system is under heavy load.  Since your battery has lost 40% of its design capacity, it may not have enough reserve left for hybrid power to function correctly.  If everything else checks out, it may be time for a new battery.

@ejn63​ Found the problem
My CPU is already at high temp when idle, already change the thermal paste and thermal pad. what could be the reason?

this is when idle, just in the desktop. and keeps like this

What happens during the diagnostics -- outside of Windows?  And what type of thermal compound OR pad (you should not be using both) did you install?

F12 at powerup to get to the diagnostics.

@ejn63​
For thermal paste I'm using Noctua NT-H1 and thermal pad using artic tp-3 

Diagnostics?
Already on it. All tests passed successfully, no error detected. Checked twice with advanced test for cpu, gpu, and both fans. All passed but the temp still high.

I would revisit your application of thermal compound and/or pads.  Do not use both together on the same device (CPU, GPU, VRMs etc.).  Use one or the other.

@ejn63​ I apply as it were the original, thermal paste only on cpu and gpu, and thermal pad on vrms.
Same like this
https://youtu.be/pzA4r4WtQwY?si=IlaxI9OHUsRjEpiB


I dont know what the problem, it looks like a dead end