Edit: Unfortunately, it seems that bumblebee is well and truly broken on the latest versions of Ubuntu 18.04, so this script no longer functions. However, at least the latest version of prime-select seems to work well again, although imo it's not as convenient compared to a grub menu option (especially when external monitors don't work in intel mode...)

I have some ideas on how the blacklisting strategy used by prime-select can be extended to provide a grub menu option. What could be done is to remove the bumblebeed.service wants from DementedIGPU.target and replace it with an ExecStart that writes a "blacklist nvidia" file to /etc/modprobe.d. There would also have to be a comparable DementedIGPU-nvidia.target file with an ExexStart that removes the blacklist from /etc/modprobe.d, and would be targeted instead of graphical.target when the user selects the Nvidia option in the GRUB menu. Sadly, I don't use an Nvidia laptop anymore so I can't test out this idea (actually, this isn't so sad at all for my sanity. But it is unfortunate for my hapless script, who no longer has a maintainer [me]).

Demented IGPU

My solution for getting Nvidia GTX 10xx laptop GPUs working on GNU/Linux, with a GRUB boot menu choice between integrated (iGPU) and Nvidia graphics. If you have Ubuntu 18.04 you can download and run the DementedIGPU Python 3 script to implement the GRUB menu (it's the only distro I tested on – my hardware was a Dell XPS 15 9560). If you have some other systemd based distribution, you may be able to run the script as-is or with some tweaking. The script tries to be smart and not just blindly overwrite your system files. And of course, you can just follow the steps below manually instead of using the automatic script.

I also have a guide (written for a beginner audience) at the bottom about installing Ubuntu 18.04 on an XPS 15 9560.

The Short Version

Download or clone this repo, unzip if needed, open a terminal and navigate to the DementedIGPU (or DementedIGPU-master) directory, and run sudo ./DementedIGPU. There's also this notify script that you can target with a keyboard shortcut in order to quickly find out which GPU is running.

If there's an issue with one step of the script, you can do that step manually and run the script for the other steps; see the sections below to see the steps that correspond to each script.

Overview

(To be clear, you don't have to read all this if you just want to run the script instead of configuring the menu manually).

My plan is to use Nvidia proprietary drivers in Nvidia mode and use bumblebee and bbswitch for iGPU mode (along with the acpi_rev_override=1 kernel option). optirun doesn't seem to work so well these days, but bbswitch seems to do a better job shutting off the Nvidia GPU than prime-select intel, so that's what I'm using. As long as we use bumblebee only when we want to keep the GPU off (instead of using it for switching), we should be okay. I do this by adding 2 GRUB menu entries: one that instructs systemd to load bbswitch (iGPU mode) and one that excludes bbswitch (Nvidia mode).

I've tried to comment and log liberally so that when you look at a line of code you can immediately get an idea of what the hell was going through my head when I wrote it. If it doesn't work for your laptop or distro, tweak it. Then fork the repo and publish your changes for everyone else; this is free software!

Step 1: Nvidia drivers

(Corresponds to part of the configure_dependencies script. Skip this if you already have the Nvidia driver of your choice installed).

For me, I installed the nvidia-384 driver. I haven't tested the script with other versions. If you're running a proprietary-software-friendly distro, this should be a fairly simple task. On Ubuntu, it's

add-apt-repository ppa:graphics-drivers/ppa
apt-get update
apt-get install nvidia-384

If your distro takes a stricter stance on free software, then I salute you, but you're on your own for this first step.

After this, if you have prime-select you need to make sure that you set it to nvidia mode! As far as I can tell prime-select intel uses a Rube Goldberg solution involving switching between nvidia and nouveau drivers and reinstalling GRUB each time a switch is done. So make sure it's in nvidia mode and not interfering with what we're trying to do!

After this step, restart the computer.

Step 2: bbswitch

(Corresponds to the other part of the configure_dependencies script).

MAKE SURE THAT YOU RESTARTED THE COMPUTER IF YOU JUST INSTALLED A NEW NVIDIA DRIVER!

Now we need to install bumblebee (which should install bbswitch). Once this is done, since we plan to enable bumblebee only when we want iGPU graphics, we need to disable bumblebee by default like so:

systemctl disable bumblebeed.service

(Note the d at the end of bumblebeed).

Step 3: Creating a systemd target

(Corresponds to the create_igpu_target_file script).

This is certainly an oversimplification, but when your systemd-based system boots, systemd looks for a target file to know what services to initialize. We want to make a new target file that's like your default target file but additionally initializes the bumblebee service. Then, we'll target this file when we want iGPU graphics.

Usually graphical.target is the default target. For some stupid reason it seems that this file can be at any odd place depending on your distro. Once you find it (possibly with a command like find /lib -name graphical.target – also try /bin and /etc I'm told), make a copy of it in the same directory. Remember the name of the copy (it's called DementedIGPU.target in the script). Then, in the Wants: line, add bumblebeed.service. It should look something like this:

Wants=your-other-services-here.service bumblebeed.service

Step 4: Modifying the GRUB menu

(Corresponds to the patch_grub_config script).

I'll just describe roughly what needs to be accomplished in this step because the exact steps depend on the specifics of your GRUB config files. We need to add a menu entry with

systemd.unit=target file name from the last step

and

acpi_rev_override=1

passed as kernel parameters. GRUB runs the bash scripts in /etc/grub.d to create its menus (the scripts write the menus to stdout and remarks to stderr). I noticed that the linux_entry function in the 10_linux file was responsible for writing a menu entry for booting the current OS. The last (4th) parameter is the list of arguments for the kernel. So I just added extra calls to linux_entry with the above two arguments tacked on at the end.

The way the script does it is that it applies the DementedIGPU.patch file to /etc/grub.d/10_linux, making a backup of 10_linux (named .10_linux in the DementedIGPU directory). So, in case the patch messed up the config file, you can run restore_10_linux_backup to fix it.

Instead of patching the 10_linux file, you may find it cleaner to create your own 40_custom file. The reason I chose this hacky 10_linux solution is that it guarantees that the iGPU entry will be updated as well along with the default entry if the GRUB configuration is changed elsewhere.

Once the file's patched, obviously you need to run update-grub and restart the computer. In my test installs I sometimes had to reboot 2 or 3 times before the system was stable. I'm not sure why this is but after those restarts the computer was completely stable (I'm eating my own dog food here; my main Ubuntu 18.04 work partition was the final test case for the DementedIGPU script).

If it still doesn't work try editing the /etc/default/grub file and removing all arguments from GRUB_CMD_LINE_LINUX_DEFAULT and GRUB_CMD_LINE_LINUX:

GRUB_CMDLINE_LINUX_DEFAULT=""
GRUB_CMDLINE_LINUX=""

Step 0: Ubuntu 18.04 on the XPS 15 9560

I decided to test out reinstalling Ubuntu 18.04 from scratch (on a different partition) to see what the UX for this script is like for a first-time user. Here's my notes from that experience. These notes probably are also useful for other Nvidia laptops.

First, follow the "Prep work with Windows" step from https://github.com/rcasero/doc/wiki/Ubuntu-linux-on-Dell-XPS-15-(9560) and disable secure boot in the BIOS. (Just for the record, I disagree with the author's assessment of Ubuntu 17.10; I thought it was a fine distro). For other laptops you'll have to adapt for this step, but after this things will probably be similar for all Nvidia GTX 10xx laptops.

Boot the laptop using a Ubuntu 18.04 live usb (Google it for instructions for creating one). Make sure all external monitors and all other usb devices are removed for this step, including USB hubs – that was the problem for me. Go into the boot menu (F12 on the XPS) and select the UEFI USB device boot option. Do NOT select legacy boot! Once you get to the GRUB menu, use the arrow keys to highlight the "Try Ubuntu Without Installing" option, and press e (not Enter).

You should be in an editor now. Use the arrow keys to go to the line that starts with linux and find the quiet splash part. Backspace that and replace it with nomodeset vga=791, then press F10 to boot.

Hopefully the computer boots after this. Once you're in, install Ubuntu as usual. Just make sure you connect to wi-fi at this point! (Unless you have ethernet, that's even better). If you want to replicate what I did exactly, I chose minimal install, no to proprietary software, and yes to updates. (Note: I never personally tested this, but it may be easier to select yes to the third-party proprietary software).

Reboot to the new Ubuntu install. Once you get to the login page, do NOT log in. It'll probably crash if you try to run a graphical system right now. Instead, press Ctrl-Alt-F3 to switch to a console and log in with your username and password.

Now for the fun part, downloading and running my script. Hopefully Ubuntu remembers the wi-fi from before. Type in

wget goo.gl/ZZxKxB

or

wget https://github.com/akeley98/DementedIGPU/archive/master.zip

to download my stuff, then run

unzip ZZxKxB

or

unzip master.zip

and finally

sudo DementedIGPU-master/DementedIGPU

to run my script. Say yes (y) whenever it asks. Hopefully this works. File a quick issue if it doesn't (although if it turns to be an issue with one of the dependencies especially Nvidia driver, there may be little I can do to fix it. File the issue anyway).

If it asks you to restart after installing Nvidia drivers, do so, then navigate back to the terminal (Ctrl+Alt+F3) and run sudo DementedIGPU-master/DementedIGPU again. (Although this time it may be safe to log in the graphical way and run the command from a terminal emulator).

Finally, run

sudo shutdown -r now

to restart, but before doing that, optionally run

sudo DementedIGPU-master/clear_default_grub
sudo update-grub

to clear your GRUB linux cmd settings.

In my experience, it took 2 or 3 reboots before the system becomes stable; I don't know why. If it's still not stable, run the above command from the Ctrl-Alt-F3 console as before (or from recovery mode).

Uninstall

To undo the file changes made by the script, run restore_10_linux_backup and restore_default_grub_backup. This restores backups made the previous time the script modified the /etc/grub/10_linux and /etc/default/grub files. If these backups aren't old enough, manually copy a backup from the backups directory to the correct location – a new backup is written each time the script changes one of those files. Run grub-update after this.

Uninstall nvidia drivers and bumblebee using whatever method your distribution requires (apt remove for Ubuntu).

Sources

Various stuff I consulted through my Nvidia graphics ordeal.

https://wiki.archlinux.org/index.php/Dell_XPS_15_9560#Power_Saving

https://bbs.archlinux.org/viewtopic.php?id=211027

https://wiki.archlinux.org/index.php/systemd#Create_custom_target

https://ubuntuforums.org/showthread.php?t=2354834#5

https://unix.stackexchange.com/questions/304085/trying-to-understand-what-a-systemd-target-wants