After the system is installed you can compile the drivers from gitlab, load their modules, blacklist nouveau, etc.
However, for that you first need to install the system, but Manjaro won’t load from recent iso’s because they don’t have the drivers for nvidia-340xx graphics cards. And no, I can’t select in the boot menu to boot with free drivers: free drivers don’t work on my machine, proprietary (old ones, from gitlab) do.
So, could anyone advise me how to get around it?
I have a working system on my old SSD (that’s how I know that free drivers don’t work with my card), however a lot of stuff has prevented me from updating the system in the last half a year or so, so if I just clone the system to the new SSD, I don’t think that I will be able to update, and anyway after such a delay it is better to just install the system afresh.
It is very rare the free driver doesn’t work with old cards - it must be very special.
The usual advise is
Use the free driver option in the installer - this will set the system to use the nouveau driver.
If it is completely impossible you can edit the kernel commandline - perhaps verify what kernel options your current install is using
cat /proc/cmdline
At the very least - you should be able to get to a desktop - then use the guide to build the old driver from the repo you mention or using the manjaro gitlab repo.
If selecting free drivers is not working on standard ISO image I suggest you try using Minimal (linux510) or Minimal (linux54) ISO Manjaro 21.3 Ruah released!
An option is trying a SbK spin. The iso’s do not contain proprietary drivers, and install with free ones. I would recommend the LXQt one with that old of hardware.
Thanks for the advice everyone! I’m gonna try them out soon.
In the meantime I found out that the installer iso can boot up with free drivers, it just takes a really long time (around 5 minutes), during which time there is no indication that something is happening — just black screen without anything. But after that the systems starts booting, which I found out by accidentally leaving the system to do some other stuff.