Introduction

usually, linux has two method to handle the dual-graphic card. The difference between them are:

Step 1. Remove Bumblebee

Usually manjaro can be easily installed choosing the free drive mode, but nouveau is hard to use. And sometimes it make user cannot entry the x-system. One way is that noting nouveau in blacklist , use command:

sudo nano /etc/modprob.d/usrBlack.blacklist

blacklist nouveau

Then to use the graphic card, one can run mhwd-tui to install the non-free driver and Bumblebee to manage dual graphic card. First of all, we need uninstall bumblebee, and may the graphic card driver installed by mhwd. One can simply remove them using the mhwd command in terminal or via Manjaro Settings Manager In other distribution, the work is the same. User can using their package manager to do it. Or more directly, do NOT install bumblebee, directly install PRIME after truning off nouveau.

Step 2. Install Closed-source Driver

One can follow the following articles to install the driver according to what he use:

• ATI to install drivers for ATI/AMD GPUs
• NVIDIA to install drivers for NVIDIA GPUs

To be careful, user should query which version of the driver is the best for their hardware.

Step3. Fix MHWD’s Configuration

this is for Manjaro Linux, for mhwd does the sensible thing and puts configuration in place as though the NVIDIA GPU was the only device available. Other distribution can jump to Step 4

1. Remove Old Config File

   Firstly, remove /etc/X11/xorg.conf.d/90-mhwd.conf (notice the su permission) , and replace it with:

   #/etc/X11/xorg.conf.d/optimus.conf
   Section "Module"
       Load "modesetting"
   EndSection
   Section "Device"
       Identifier "nvidia"
       Driver "nvidia"
       BusID "PCI"
       Option "AllowEmptyInitialConfiguration"
   EndSection
   

   While the BusID value can be find by command: lspci | grep -E "VGA|3D"

2. Write Blacklist One need to remove two files: /etc/modprobe.d/mhwd-gpu.conf and /etc/modprobe.d/mhwd-nvidia.conf and write a new one:

   blacklist nouveau
   blacklist nvidiafb
   blacklist rivafb
   

Step 4. Enable nvdia-drm.modeset

PRIME relies on vidia-drm , one need to creat a new file:

#/etc/modprobe.d/nvidia-drm.conf

options nvidia_drm modeset = 1

Step 5. Make dGPU as primary

First for other distribution but manjaro, user need to edit the file /etc/X11/xorg.conf , if X.Org and X server version 1.17.2+

#/etc/X11/xorg.conf

Section "Module"
    Load "modesetting"
EndSection

Section "Device"
    Identifier "nvidia"
    Driver "nvidia"
    BusID "PCI"
    Option "AllowEmptyInitialConfiguration"
EndSection

Next, add the following two lines to the beginning of your ~/.xinitrc :

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

However, if user is using a display manager , then he should create or edit a display setup script for his DM instead of using ~/.xinitrc , this is different among main DMs, for the most three popular: (We assume user has stored the command above in a .sh file as optimus.sh and adjusted the permission)

1. LightDM Edit the file /etc/lightdm/lightdm.conf :

   [Seat:*]
   display-setup-script = optimus.sh
   

2. GDM GDM is the defult display manager of Gnome 3 . one should create two new .desktop files:

   #/usr/share/gdm/greeter/autostart/optimus.desktop
   #/etc/xdg/autostart/optimus.desktop
   
   [Desktop Entry]
   Type=Application
   Name=Optimus
   Exec=sh -c "xrandr --setprovideroutputsource modesetting NVIDIA-0; xrandr --auto"
   NoDisplay=true
   X-GNOME-Autostart-Phase=DisplayServer
   

   Or user can create one and link those two by command ln -s

3. SDDM SDDM is the default display manager of KDE . one should write those two command to file /usr/share/sddm/script/Xsetup like:

   #/usr/share/sddm/scripts/Xsetup
   
   xrandr --setprovideroutputsource modesetting NVIDIA-0
   xrandr --auto
   

Step 6. Reboot

If everything is set correctly, when user reboot, DM will load and he can log in. And:

$ glxinfo | grep -i vendor
server glx vendor string: NVIDIA Corporation
client glx vendor string: NVIDIA Corporation
OpenGL vendor string: NVIDIA Corporation

References

1. PRIME - ArchWiki
2. NVIDIA Optimus - Arch Wiki
3. [HowTo] Set up PRIME on Manjaro