Have you upgraded your video card without also upgrading your PC power supply?
Do other games cause a reboot?
If the above does not help, please post your Dxdiag report here, thanks.
Battlefield Player on PC, Xbox One, PS4, Xbox 360, PS3
BF3, BF4, BF1, BFV DICE Friend tag awardee
SWTOR Player on the Hot Prospect (Satele Shan), Star Forge, and Darth Malgus