The computer randomly restarts, what to do?

The computer hangs for a second, then restarts.
This occurs most often when watching videos in the browser, it can also happen in normal usage of the PC.
Temperature - normal. Under load, not shown, formaram test and cinebench at the same time - no restarts. Wood for vidyuhi rearranged - did not help.
Prompt where to dig?
My setup:
ryzen 1700
gtx 650ti
Ddr4 16gb (2x8)
gigabayte b350
April 7th 20 at 15:17
4 answers
April 7th 20 at 15:19
Start with memory. Drive memtest.
April 7th 20 at 15:21
Option RAM.
First try to work with 1 strip at a time.
Then without a video card, if there is built-in.
If still restarts - you need the power supply the other to put to test.
Also check for swollen capacitors on the motherboard
April 7th 20 at 15:23
Maybe the PSU is faulty, and maybe memory, a bunch of options. As for me it is best to diagnostician to throw to the slam dunk to understand
April 7th 20 at 15:25
The type and version of the OS in question is not specified, but if it was about furmark and cinebench, it Windows.

Go to control Panel -> System -> advanced system settings -> Advanced tab -> startup and recovery, uncheck the item "automatically restart" and check the box for "write an event to system log". The memory dump can not touch. Then wait for the next reboot.

First, you need to find out whether there will be any BSOD and the error number will be written on it. If not mistaken, the default Win10 output the error number is disconnected. How do I enable it specified, for example, here. Secondly, after restarting, go to control Panel -> administrative tools -> computer Management -> event Viewer -> Windows logs -> System and see over time what errors or mistakes happened just before reboot. This will give food for further reflection.

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