Question PC freezes everytime after 1 minute

[Arthur99]

Everytime I boot up my new pc build no matter whether it's windows or Ubuntu after about a minute everytime it slows for a second then freezes leaving me unable to do anything but power off. It works fine in Bios and CPU temps in bios are fine and worked in memtest86 but windows or Ubuntu freezes after a minute. Ive been struggling for about 2 weeks It would mean the world if someone could help me with this as it's a pc for Christmas for my son.
The specs are
Gtx 1660 ti
Evga 750 watt power supply
Ryzen 5 2600
2x 8gb killsre ram 3200 Hz
Asrock b450m hdv r4.0 mobo

 

[NightHawkRMX]

Try setting bios settings to default.

 

[Arthur99]

Try setting bios settings to default.

I tried that didn't help, thanks though