It might be a temperature issue. Try monitoring them.
If all fine, test a different PSU. The shuts down might not be related to the BIOS update.
I tried playing a game the graphics card temp was between 40 celsius to 60 celsius but it was only at 47 celsius when the computer shuts down. The CPU and CPU sockets were at 48 and 49 celsius. I also noticed that theres a alert on every startup since the last BIOS update that OPT fans are abnormal.