Try to reset BIOS to as his factory settings.
-+Hold down Ctrl+Home then power button.
-+HOLD Ctrl+Home until you see EZ-Flash starting. (Holding it could be around 20 SECONDS)
-+Wait till the factory reset is finished. at the end it will say restart in two seconds.
-+Laptop shutdowns automatic (DO NOT INTTERUPT THIS PROCESS)
-+When it's done start the PC
MAKE SURE YOU HOLD THESE KEY"S at stap 1-2
ACER PREDATOR G9-791 |Intel Core i7-6700HQ |16 GB RAM |GTX970M 3GB |FULL HD | 750GB SSD | Samsung 850 PRO & 2X M.2 SSD RAID 0
G75VW |Intel Core I7-3610QM |24GB RAM |GTX670M 3 GB |FULL HD | 526GB SSD | Samsung 840 EVO & 850 PRO
GL552VW |Intel Core i7-6700HQ |12 GB RAM |GTX960M 3GB |FULL HD | 256GB SSD | Samsung