Why does the image disappear during games?

Question

Video cards

In general, for some reason, in some games, the image may suddenly disappear for me (while the system is working, and sometimes there is even sound, and it happens that the PC immediately reboots), while in the logs the temperature of the processor and vidyuhi are normal. I also loaded the PC with Aida (system stability test) - 10 minutes of normal flight, as well as Furmark. There are suspicions about the lack of power of the PSU, but why then the image does not disappear in the tests and everything is fine. This happens not in one game, but in many.

System configuration:
Xeon e3 1230 v2
gtx 950
8gb ram
ssd kingston 240gb
motherboard P8B75-V
PSU claimed 400 watts

Answer 1

Perhaps due to video out of sync, you can try changing the monitor to 144 Hz or 240 Hz.