Steam overloads PSU??

J158

Honorable
Dec 27, 2012
1
0
10,510
Hello,
I have just built a PC for my Son. Everything seems to work fine until he goes to play Team Fortress 2 on Steam. The Motherboard then resets, and restarts the PC. The error message then stats this is an overload issue with the PSU. The PSU is an Artic Blue 750w / 850w type. Is this really at fault? It works fine for normal PC functions. I read somwhere that it could be the Bios on the Motherboard (Asus M5A78L-M-USB3). I upgraded this to a new version (1503). The problem is still there.
Just for reference the Motherboard has an AMD FX 8150 8 core 3.6Ghz processor and 8GB RAM on it. Has anyone else seen this before, or knows whats going on?
Thanks In Advance.

J.