ASus G750jx Shut down abruptly while playing Games

[Arun kumar]

Dear Friends,

While playing Games like Battlefield 4 ,FAr cry 4 and FIFA 15, My Asus G750JX shut down abruptly.

GPU Temp--> 78 C

GPU USage --> 99 %

Memory clock speed --> 4010 MHZ,

PLease let me know , what could be the reason .

Thanks,
Arun