When the steam starts, the computer restarts. Critical kernel-power error 41 (63)

After the next steam update, the computer began to knock out to reboot. At startup, there is a check for updates, followed by a logpass window, a couple of seconds (you can even type characters) and a black screen, reboot and in a circle. As I understand it, Steam itself does not criticize, but because of it, the system gets it.
I tried to reinstall Steam.
Reinstalled Windu.
I checked the crystaldiskinfo hard drives - good condition.
I checked the RAM - it's normal.
I ran the hardware through Prime95 - half an hour is stable, without errors, I did not go further.
I tried to run it offline - the same thing.
Everything else runs flawlessly.
I applied to support Steam, they said that our powers are all.
Maybe someone came across this? Hands are already down