Success! That was exactly the clue I needed; thankyou. In case anyone else is reading this because they have the same problem:`boot -c` got me a boot menu, but it wasn't accepting input from my USB keyboard, so I couldn't use the full set of commands from there.
What did work was: - At the boot menu, select option 2. - Enter `userconf disable nouveau`.- Enter `menu` to return to the original boot menu. - Press 1 to boot into the installer. - After running the installer and rebooting, you need to repeat the first 4 steps at the boot menu, to disable Nouveau and boot the system. - Edit `boot.cfg` (the documentation says it's `boot.conf`) and add the line `userconf=disable nouveau` - Probably reboot at that point, to verify that it works. My apologies for top-posting, but this web interface doesn't have an obvious way to properly edit this message as plain text. Thanks again, Kat Oct 18, 2026, 00:19 by [email protected]: > On Sat, 17 Oct 2026, [email protected] wrote: > >> The initial installer menu loads fine, and pressing "1" gives the usual >> stream of system-probe messages, so that much works perfectly well. When >> sysinst tries to present its TUI, things go immediately to pot. >> A couple of green and magenta horizontal lines appear over the text near the >> top of the screen, and the bottom quarter initially flashes with some >> green-on-black garbage, which is quickly replaced by slowly evolving >> white-on-blue garbage. I take this to be a disagreement between the GPU and >> the driver selected by the installer. >> > > Most likely a DRMKMS driver issue. Try disabling `nouveau'[1]. At the > bootloader > prompt: > >> userconf disable nouveau* >> menu >> > > -RVP > > [1]: > https://wiki.netbsd.org/tutorials/x11/how_to_use_wsfb_uefi_bios_framebuffer/ >
