Since DELL-Support was not able to help because there were no overheating issues logged in UEFI itself, I came to the conclusion that it must be something like a too aggressive threashold temperature in the Intel Dynamic Tuning driver which caused my shutdowns via software. As soon as my graphics card got 80°C, it went into hibernation mode. I had to uninstall the Intel Dynamic Tuning driver and disable its Windows service to get rid of this problem. The graphics card now goes up to 86°C without shutting down and the system itself is then able to bring the temperature back down to 75°C while under full load.
Hi all, I have my Precision 5550 with an Core i7-10875H and a Quadro T2000 since January 2021 and it was performing quite well. Throttling always has been an issue, but in the whole time I'm using it, it only shutdown once because of thermal overheating when rendering a 3D Blender file with CPU and GPU for about one hour. But in the last two days I realised, that I can't even get Blender to render for one minute without the Laptop shutting down. Yesterday and today I had at around 8 shutdowns (to be exact the Laptop goes into hibernation mode) which is unacceptable for a "Workstation" Laptop. Please also note that I am using this machine in an air conditiond office, so even hot days in Europe/Austria can't be the issue... The following event is logged to Windows when overheating occurs: For me it looks like that there is something wrong with one of the last BIOS updates. The laptop was working quite fine and now I can't event get one Blender render to completion. My current BIOS version is 1.17.0. I have the option "Optimized" enabled in the Dell Power Manager. Also tried "Ultra-Power" which is even worse. Does anyone else have had increased occurences of this thermal shutdown in the past?  
Precision 5550 overheating issues since BIOS Update(?)