If your motherboard is legacy BIOS only (non-UEFI) then that's almost
certainly the problem and messing with GRUB won't help. There are a
couple of easy ways to go about it:
-Return your card,
-Upgrade your whole system;
and a couple of not very easy and not guaranteed to work:
-try booting with your 5700 in a secondary PCI-E slot and your old GPU
in the main slot, check if Debian detects both video cards, force
certain applications to use new video card and use it like this if it works.
-check if there is a different BIOS available for your new GPU which
enables legacy support.
On 2020-12-27 00:19, The Wanderer wrote:
I have for some years been running Debian with an older model of AMD GPU
(Radeon HD 6870) for graphics.
I recently purchased a relatively recent model of GPU (Radeon RX 5700
XT), and today swapped it in and attempted to boot with it.
I was expecting to get no graphics support (e.g., X, et cetera) until
after adjusting some combination of installed driver- and
firmware-related packages, module-blacklist settings, boot-time options,
initrd state, GRUB configuration, and possibly other (again, e.g., X)
config files. I'm generally fine with wrangling that, and based on my
pre-swap research, was expecting to be able to get up and running with
the new GPU today.
What I got, instead, was not even that far.
With the new GPU in place, I get video output during POST and in the
BIOS (yes, this machine is old enough that it doesn't have a UEFI)
without problems. That demonstrates that the GPU isn't dead on arrival,
and that signal is getting through to the monitor on a basic level.
However, as soon as the machine tries to hand over control to the
bootloader, I get a hard freeze; the screen goes black (albeit I think
still with backlight), the keyboard light toggle keys stop responding,
and the GRUB menu never appears. Waiting a long time doesn't change
anything; even after roughly half an hour of waiting, pressing the Power
button once (no press-and-hold) shuts the system off immediately, which
indicates that the system hasn't progressed much (if at all) past early
boot.
Thus far, Google has not been helpful. I find plenty about black screens
after GRUB, but very little about before GRUB and after POST, and what
little I find is from other distros - some Ubuntu (earlier versions,
mostly 2010-era), some Arch, some RHEL - which don't necessarily handle
either graphics drivers or GRUB in a way that will let their directions
reliably translate to Debian.
Any suggestions for what to try?
I'm back up now with the old GPU, since researching this on my
smartphone was going nowhere. I've dug into /etc/grub* and /boot/
looking for anything which seemed related, with no promising hits yet.
Barring other discoveries, my current next step is to dig up a suitably
recent Debian-based live-boot environment, boot to that, and see what it
does. If it gives me usable graphics, I want to see what it's doing at
bootloader time, and what parts I might be able to transpose into my
primary install.
However, given that live-boot setups don't always handle the early parts
of boot the same way as hard-drive installs do, I'm not positive this
will be fruitful. Also, given how relatively new this card is, I'm not
sure I'll be able to find a suitable environment which does work with it
to the level I need.
--
Pagarbiai
Romualdas Taluntis
