ThinkPad P15 Gen 1 enters in heat protection too early

[tmm360]

Hello everyone.
I've this notebook, and I'm loving it, but with some more heavy games it starts to lag very soon, even if it would be able to run without any problems. I've a Quadro GTX 5000 GPU (Nvidia drivers 472.42), it's very powerful and can run near everything in Ultra, but with some games after a while it starts to lag.
It happened with Doom Eternal in Ultra with RTX, Flight Simulator in VR and Cyberpunk 2077 (with every configuration).
Temperatures don't look too high, higher is the GPU around 55, but I'm testing it with SpeedFan (probably a very old software...). The fans don't spin too fast, probably can go faster, and trying to put hand in front of the heatsink it doesn't appear "too hot".
Anyone have identified issues like this? Should I ask to assistance? What's you preferred software for diagnostic temperatures? Thanks!