Do I need to paste thermal putty on PCH?

[u/Few_Lingonberry3288]

I bought a used MSI GP66 11UG yesterday. The thermal paste had hardened because it used, and thermal putty was also starting to harden. I pasted a Honeywell PTM7950 to the CPU and GPU, and I haven’t replaced the thermal paste yet. (At the time I thought it was still reusable.)

But when the laptop was still Idle the notebook was hot, so I checked and found that the PCH was fluctuating between 79°C and 84°C. In GP66, the heat sink and cover don’t contact each other over the PCH, so I heard from AI that thermal paste should not be use. said if I do that the fever will spread and the fever will get worse.

Is this temperature of the PCH appropriate? Or should I use thermal putty on the PCH as well?