if not slot in properly cannot boot
uppdate driver
does it happen to other games too? when gray screen com hang need restart?
Maybe vga card going up lorry?
Need some help here. Sometime play game halfway then gray screen.
Revert every setting to stock first.
Remove all AMD drivers (including folders and regedit). Install previous Drivers and see how it goes.
gfx chip overheatin
run a 3d benchmark program it will show u the temp
keep an eye and see ow high the temp rise b4 it reboot or hung