@socksinspace & @birdgoose, thanks for your advice!
Unfortunately I wasn't able to install NetBSD. The computer always rebooted a few seconds after the apparition of the first blue screen. I tried to install OpenBSD, it worked but I did not succeed to connect my computer to the Internet, even with an Ethernet cable connected (skill issue, I presume). So I tried Gentoo but the installer froze. Desperate, I installed Debian Bookworm and everything worked on the first try… such a pity that they don't support 32bit architecture anymore!
My quest for a modern OS for my 2005 computer is not finished. Maybe I'll try Parabola next.