Install Linux Mint 19.1 Xfce on HP Pavilion Gaming 15 (cx0812no)...

USB Stick

Download linuxmint-19.1-xfce-64bit.iso.
Use Rufus to create the USB stick: rufus-3.5.exe.

BIOS Settings

Disable every "Secure Boot" and "TPM" security feature.
Enable USB boot and increase the time it waits during boot to 5s (time to press Esc).

Installation and First Boot

Install Mint and during the first boot press Esc and the continue the boot by pressing Enter and quickly press Shift to enter Grub menu. While in the Grub menu, press 'e' to edit the boot settings and change "quiet splash" to :

"quiet splash nomodeset"

If you fail to enter Grub menu then a hard boot will be needed in the login screen because the system will hang without the 'nomodeset'. Once it is set, reboot and enter the desktop and make the nomodeset permanent:

sudo nano /etc/default/grub
sudo update-grub
reboot



Install applications, Update and Create Backup

Using the friendly popup screen at the startup, DO NOT install drivers at this point, install the applications you think you might need, update the system and reboot to see if it still works after that. If it works then create a backup of the system with the backup manager.

Install NVidia Driver

Now that there is a backup to restore to if the driver installation fails, install the latest nvidia driver (390) using the driver manager and reboot. Once rebooted, use the following command to check that the driver installed correctly:

lsmod | grep nvidia

If you see a bunch of nvidia entries in the output, everything is ok (the system is still broken but the driver is there). The next thing that needs to be done is to add xorg.conf:

sudo nano /etc/X11/xorg.conf

Section "Module"
  Load "modesetting"
EndSection

Section "Device"
  Identifier "nvidia"
  Driver "nvidia"
  BusID "PCI:1:0:0"
  Option "AllowEmptyInitialConfiguration"
EndSection

After that, create a script that changes the mode to the discrete GPU when X is started:

sudo nano /usr/local/bin/optimus.sh

xrandr --setprovideroutputsource modesetting NVIDIA-0
xrandr --auto

sudo chmod a+x /usr/local/bin/optimus.sh

Then the script needs to be added in the display manager's startup config:

sudo nano /etc/lightdm/lightdm.conf.d/70-linuxmint.conf

[SeatDefaults]
display-setup-script=/usr/local/bin/optimus.sh

The last thing that needs to be done is to remove the 'nomodeset' that was added at the beginning:

sudo nano /etc/default/grub

"quiet splash"

sudo update-grub
reboot

Create another backup and enjoy the roaring fan of the discrete nvidia GPU...

After everything works, but all animations in the game run slow, uncheck Sync to VBlank and Allow Flipping in OpenGL Settings in NVidia X Server Settings.