why my nvidia driver pack is missing on my acer predator helios 300 PH315-51?

Try to do a Hard Reset by taking the back cover off and then taking the main battery out and then disconnecting the RTC/BIOS battery, and afterwards you need to shot the +&- pins of the bios battery plug at the mainboard to reset CMOS, take the ram out also, leave the laptop like that (preferably overnight) but try for 1 hour and then reconnect all components and with the ram only use 1x ram module and see if the NVidia gpu appears, as this resets the EC and chipset chips that could be frozen in your laptop and that is why its not detecting the gpu.

Try that and if it doesn't work then you have some issues and maybe a burned mosat and a gpu that you need to take your laptop to a technician to diagnose, as if its that mosat that regulates the voltage to the gpu the gpu burns out, or your laptop has some main rail power issues that affect the gpu and that is why the gpu is not working, but you can use the laptop with the Intel HD graphics but if you want your laptop with its dedicated gpu, you need to either have it checked out or change the mainboard. Good luck and hope this has helped you out.

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