Pc power cycles

[RedNick]

My son's pc randomly started to power cycle but I can get into the bios and it will stay there no problem its only when it tries to boot it seems.

[OddOod]

Sounds like a PSU issue

[zipspence]

1 hour ago, RedNick said:

My son's pc randomly started to power cycle but I can get into the bios and it will stay there no problem its only when it tries to boot it seems.

Few things to look at here. It could be the PSU like OddOod said, but to expand on other things it could be... 
1. when in bios check to make sure all components of the system and registering and showing up. If something is missing it could be a component failure, SSD, Ram, cooling etc. 

2. Next check your boot order and boot config, silly enough we had an issue at our company a bit ago where after an update come out it would randomly switch the SSD operation to raid instead of being in NVMe. 

3. Go back to the basics. step by step remove 1 component after another until you get a boot, I normally start with ram and extra Hard drives to make sure nothing involved there is a factor. After that put the Computer back onto its on-board graphics and remove the video card, this will at minimum make sure nothing secondary is happening when the system checks are being performed. With the base minimum installed, if it will boot, then its a component failure, if it wont boot after that, you could have a bad SSD/corrupted hard drive not allowing a boot, after that with all that work done, you can try a CMOS reset, and after that I would go after a PSU replacement.