I have the exact same problem. But i did not do it on the main menu. I was ingame already.
And it seems Witcher 3 can overheat my system and i DON'T KNOW WHY!
My rig: all hardware just 5 weeks old.
- Intel i7 4790k (4Ghz) + Scythe Mugen 4 Cooler
- Gigabyte GA-Z97X-Gaming 3 (BIOS up to date)
- Gigabyte GTX 970 G1 Gaming (BIOS up to date)
- 16 GB RAM
- Corsair Graphite 600T (2x 200m cooler + 1x 120mm cooler) Airflow should be fine(!)
Witcher 3 settings:
- 1080p fullscreen, Ultra preset
- Frame limiter to 60
- Hairworks OFF
- All postprocessing effects OFF, except Light shafts
--> Result:
55-60 fps <- i was happy with that!
But...
TEMPERATURE (taken by hwmonitor):
CPU: Idle ~24° C -> Max. 72° C
GPU: Idle ~27° C -> Max. 78° C
Both CPU and GPU are way too high imho.
I can also confirm a 99% GPU load while i was alt+tab'd.
I even got 2 BSOD (!) while i was alt+tab'd on the desktop and the game still running in the background. I did not analyze the crashdump files yet, so i cannot tell if its related to overheat. But so far i never had any bluescreens in other games yet.
Still don't know what the problem is... 60 fps, no stuttering, no frame drops, rare crashes-to-desktop... but i can't find a solution for the high temperature (which is way higher than its supposed to be)
GTA 5 @ Ultra settings (no MSAA) is running perfectly fine and the system does not seem to generate any noticeable heat. Its cool.
Would be grateful for any suggestions how to approach this problem.