Just did some more testing, its as you say Bonnom, i started the tablet up entered XTU and started running the benchmark.
The first run it managed to go the full 3 minutes without throttling, directly started a new test and it went for about 2 mins before starting to power limit throttle.
There must be some kind of temperature sensor on the MB that starts the throttling, my CPUpackage newer goes over 71C, so thats not a problem but the backside of the tablet heats upp over time.
Also, would it be safe to disable the power limit throttling? Maybe some other components cant take the heat.
Need to look if i have a usb keyboard laying around somewhere so i can get into the bios.
The thing is you might get descent benchmarks running tests up to ~5mins after that the throttling will really kill the performance.
What values are you using in the BIOS to get it disabled?