It did not overheat. The power supply just could not handle the load and shut itself off.
It is a standard problem with the stock supplies: they run at the very very limit of their capacity.
You have three options to avoid this in the future:
1. Run in a cooler room
2. Slightly reduce the frequency, say from 196 to 190.
3. Upgrade to a more powerful PSU, say 1200W

Good luck!