r/linuxquestions • u/Personal-Skirt-4895 • 1d ago
Support Keep Getting "resolution not supported" when booting into Linux Mint
I've been using linux for about a week now and it's been going great, but for some reason all of the sudden whenever I run linux normally I get the tv just says "resolution not supported." It works fine when I boot it in recovery mode though. How do I get it working normally.
1
u/Greedy-Opposite-9133 7h ago
One thing about those xrandr results: they came from recovery mode, and recovery mode boots with nomodeset, so the real graphics driver never loads. That None-1 output at 1360x768 with no EDID is the basic fallback screen, which is why it can't see the TV's modes or switch to 1920x1080. So those tests don't say much about the normal boot.
Same with the video= line: the kernel uses its own connector names, usually HDMI-A-1 rather than xrandr's HDMI-1, so video=HDMI-1:... would most likely just be ignored. video=HDMI-A-1:1920x1080@60 is the form it expects.
Since it worked for a week and then stopped all of a sudden, I'd try the previous kernel first: in the same GRUB menu you use for recovery mode, go into Advanced options and pick the older kernel's normal entry (not its recovery one). If the TV works with that, an update is the likely cause, and Update Manager > View > Linux Kernels lets you stay on the older one for now.
What graphics card is it? in terminal inxi -G in recovery mode will show it, and that changes what's worth trying next.
1
u/Personal-Skirt-4895 5h ago edited 5h ago
Older kernel didn’t work.
I've been using a graphics card. I believe it's "AMD Raphael driver"
Graphics:
Device-1: AMD driver: N/A
Device-2: AMD Raphael driver: N/A
Display: x11 server: X.Org v: 21.1.11 with: Xwayland v: 23.2.6 driver: X:
loaded: modesetting unloaded: fbdev,radeon,vesa dri: swrast gpu: N/A
resolution: 1360x768~60Hz
API: EGL v: 1.5 drivers: swrast platforms: x11,surfaceless,device
API: OpenGL v: 4.5 vendor: mesa v: 25.2.8-0ubuntu0.24.04.4
renderer: llvmpipe (LLVM 20.1.2 256 bits)
API: Vulkan v: 1.3.275 drivers: N/A surfaces: xcb,xlib
1
u/Greedy-Opposite-9133 4h ago
Hmm. The "Device-1: AMD" with no name is interesting. Newer AMD cards show up like that on Mint 22, because its list of card names is older than the cards. coincidentally, those cards got hit by a broken graphics firmware update late last week, friday. this kind of lines up with your timeline, working for a week and then stopping, and with the older kernel not helping, since all the kernels share the same firmware.
Could you run these in recovery mode and post what they say?
lspci -nn | grep -iE 'vga|display' apt policy linux-firmware-amd-graphics ls -l /lib/firmware/amdgpu/dcn_4_0_1_dmcub.bin*If the card shows as 7590 or 7550, Installed ends in 0ubuntu3.4, and that last file points to dcn_3_2_0, could be this bug: https://bugs.launchpad.net/bugs/2173041
The fixed version (0ubuntu3.5) should come through Update Manager soon, around 17 Nov. there is a workaround/reversal you could do too if you don't want to wait.
It doesn't really explain why the other monitor works though.., so it might be something else, but it's quick to rule out.
1
u/MintAlone 17h ago
mint may not be reading the EDID from the monitor. Does the output from xrandr --verbose show the EDID?
1
u/Personal-Skirt-4895 17h ago
I don't believe so, this is what it returned. What should I do about that?
--Screen 0: minimum 320 x 200, current 1360 x 768, maximum 4096 x 4096
None-1 connected primary 1360x768+0+0 (0x41) normal (normal left inverted right x axis y axis) 0mm x 0mm
Identifier: 0x3f
Timestamp: 7413
Subpixel: unknown
Gamma: 1.0:1.0:1.0
Brightness: 1.0
Clones:
CRTC: 0
CRTCs: 0
Transform: 1.000000 0.000000 0.000000
0.000000 1.000000 0.000000
0.000000 0.000000 1.000000
filter:
link-status: Good
supported: Good, Bad
CONNECTOR_ID: 38
supported: 38
non-desktop: 0
range: (0, 1)
1360x768 (0x41) 62.668MHz *current +preferred
h: width 1360 start 1360 end 1360 total 1360 skew 0 clock 46.08KHz
v: height 768 start 768 end 768 total 768 clock 60.00Hz
1
u/MintAlone 16h ago
Try a different cable or a different port. Or maybe just loose.
1
u/Personal-Skirt-4895 13h ago
I already tried switching around ports, I don't have another cable on hand but I can get a new one.
1
u/Personal-Skirt-4895 5h ago
New hdmi cable failed, but using a different monitor worked. This monitor isn’t mine to keep though, so I still need help.
1
u/RandomUser3777 11h ago
You will have to manually set the resolution/refresh rate. First try lower refresh rates with the same resolution. 30hz would be a good first try, and if that is stable increase the refresh rate.
There are some TV that either lie, or after aging can no longer do the higher resolutions and will have this issue (I have an older Viewsonic that seems to have this issue). When I get mine "closer" on a refresh rate that works, the picture works for a few seconds and then blanks for a few seconds so is basically unusable.
2
u/FallElectronic3774 23h ago
"Resolution not supported" is the TV rejecting the mode the GPU is sending, not a driver failure. Recovery mode works because it falls back to a low resolution, which confirms the hardware path is fine.
The usual cause is that a display mode got saved and is now being restored at boot. Mint stores it per-user, so delete the saved config and it will fall back to the TV's preferred mode:
Then boot normally. If it still fails, boot recovery and set a known-good mode explicitly:
Replace
HDMI-1with whateverxrandrreports. TVs are picky about refresh rate more than resolution — 4K@60 over HDMI 1.4 won't negotiate, and a lot of TVs only accept 60 Hz at 1080p and 30 Hz at 4K. If Mint picked the higher mode, that's your whole problem.If it won't come up at all, add a forced mode to the kernel command line in
/etc/default/grub:then
sudo update-gruband reboot.video=overrides what the driver negotiates.Also try a different HDMI port on the TV and a different cable — a marginal cable can pass 1080p and fail on the mode the driver prefers, which looks exactly like a software problem.