I noticed by looking at the watt consumptions of the graphics, when I get into Fortnite it starts to drop to 22watts (when on desktop it consumes 25watts) and loading other games it goes up to 30watts and playing at 100watts. It makes sense that this is the problem that causes my PC to reboot, because my PC reboots after Fortnite has loaded all the files and proceeds to show me the lobby graphically, this graphical demand is not abastasized with the little power it receives. I have the latest version of AMD adrenaline.
I want to add I found other guy who has the same problem as me with the same graphic card. The weird thing is the problem has been getting worse, At first it restarted 10 minutes after playing and now it is before showing me the lobby.