Arch Linux

perhaps try blacklisting the dgpu driver? https://wiki.archlinux.org/title/Kernel_module#Using_kernel_command_line_2

I managed successfully to make it work with udev rules in the past. https://wiki.archlinux.org/title/Hybrid_graphics#Fully_power_down_discrete_GPU

Have you checked in the bios to see if you can turn it off ?

Can you disconnect the dGPU physically?

Damn that's not the easiest problem. I dont have any solutions unfortunately but have you tested any distros with graphical installers? I'm curious if any of them solve this or if they behave the same as windows.

If software methods won't help, you can google smth along the lines of "$laptop_model uma"; usually disabling dgpu in hardware is quite simple, like lifting one coil

It's probably the other way around, the dedicated GPU is problematic (needs reballing most probably) and the onboard one (on the CPU) is OK. Try to find a hacked BIOS for the laptop that completely disables the dedicated GPU. There were some models that just needed a modded BIOS for this. Others required some hardware intervention as well.

You’ll need to go into bios. There should be an option to disable the dgpu, or it’s possible you’re in optimus mode

What laptop is it? On some, not many, you can remove the dgpu. If you can access the bios, it wouldn't hurt to see if you can set priority order for the gpu used. What do you mean you can't get past choosing the installation medium? To me that means the usb, iso, etc you are using. I'm probably misunderstanding you, but do you mean selecting the medium in the bios boot screen? Or have you gotten to the part where grub shows up and you can select install. If it's the bios bit, have you turned off secure boot? If it's after selecting install arch in the grub menu, wait a tiny bit for everything to load and try pressing ctrl-alt-F3. Doesn't have to be F3 you can try all the "F" keys. This will switch to a different tty to try and see if the default one is being weird Though I doubt that will help, but worth a shot. If you can get to grub have you tried to disable the kernel module that loads for the dgpu? You should be able to press "e" to go to the bit you can edit stuff in grub. Check out this and see if it helps https://wiki.archlinux.org/title/Kernel_module#Using_kernel_command_line_2 Best of luck!