You are not logged in.
I bought a new display a few days ago. It supports 4K, 120Hz via HDMI 2.1, 144Hz via Display Port 1.4,
The card in my computer is a AMD RX 550 with HDMI 2.0 and Display Port 1.4, I am using the open source xf86-video-amdgpu driver and have connected the display via DisplayPort.
[sapiens]$ xrandr -q
Screen 0: minimum 320 x 200, current 3840 x 2160, maximum 16384 x 16384
DisplayPort-0 connected primary 3840x2160+0+0 (normal left inverted right x axis y axis) 697mm x 392mm
3840x2160 60.00*+ 60.00 59.94
2560x1440 143.86 119.88 59.94
1920x1080 143.85 120.00 119.88 60.00 60.00 59.94
1680x1050 59.95
1280x1024 60.02
1440x900 59.89
1280x720 120.00 100.00 119.88 60.00 50.00 59.94
1024x768 75.03 60.00
800x600 75.00 60.32
720x576 50.00
720x480 60.00 59.94
640x480 75.00 60.00 59.94
HDMI-A-0 disconnected (normal left inverted right x axis y axis)
DVI-D-0 disconnected (normal left inverted right x axis y axis)
[sapiens]$
As you can see xrandr only recognizes the display to be 4K/60Hz capable.
I tried the following:
[sapiens]$ cvt 3840 2160 144
# 3840x2160 143.94 Hz (CVT) hsync: 338.25 kHz; pclk: 1829.25 MHz
Modeline "3840x2160_144.00" 1829.25 3840 4200 4624 5408 2160 2163 2168 2350 -hsync +vsync
[sapiens]$ xrandr --newmode "3840x2160_144.00" 1829.25 3840 4200 4624 5408 2160 2163 2168 2350 -hsync +vsync
[sapiens]$ xrandr --addmode DisplayPort-0 3840x2160_144.00
[sapiens]$ xrandr -q
Screen 0: minimum 320 x 200, current 3840 x 2160, maximum 16384 x 16384
DisplayPort-0 connected primary 3840x2160+0+0 (normal left inverted right x axis y axis) 697mm x 392mm
3840x2160 60.00*+ 60.00 59.94
2560x1440 143.86 119.88 59.94
1920x1080 143.85 120.00 119.88 60.00 60.00 59.94
1680x1050 59.95
1280x1024 60.02
1440x900 59.89
1280x720 120.00 100.00 119.88 60.00 50.00 59.94
1024x768 75.03 60.00
800x600 75.00 60.32
720x576 50.00
720x480 60.00 59.94
640x480 75.00 60.00 59.94
3840x2160_144.00 143.94
[sapiens]$ xrandr -v --output DisplayPort-0 --mode 3840x2160_144.00
xrandr program version 1.5.1
xrandr: Configure crtc 0 failed
Last edited by Sapiens (2023-01-07 16:50:06)
Offline
Offline
Does your cable support that resolution?
I only have two DisplayPort cables, one came with the monitor. Just to make sure I have ordered an additional cable from Club3D. Those are supposed to be high quality.
Last edited by Sapiens (2021-11-21 19:41:30)
Offline
Please identify the output (vendor/model), post your xorg log, https://wiki.archlinux.org/title/Xorg#General and try
% cvt12 3840 2160 144 -b
# 3840x2160 @ 144.000 Hz Reduced Blank (CVT) field rate 144.000 Hz; hsync: 333.216 kHz; pclk: 1306.21 MHz
Modeline "3840x2160_144.00_rb2" 1306.21 3840 3848 3880 3920 2160 2300 2308 2314 +hsync -vsync
Offline
% cvt12 3840 2160 144 -b
4k/144 is not possible with this graphics card.
DP1.4 (HBR3) is just enough to run the reduced blanking v2 modeline for 4k/120hz.
HDMI 2.0 is at the limit with 1440p/144hz or 4k/70hz at maximum reduced blanking
Limits checked with
https://tomverbeure.github.io/video_timings_calculator
4k/120 created with cvt12:
$ cvt12 3840 2160 120 -b
# 3840x2160 @ 120.000 Hz Reduced Blank (CVT) field rate 120.000 Hz; hsync: 274.440 kHz; pclk: 1075.80 MHz
Modeline "3840x2160_120.00_rb2" 1075.80 3840 3848 3880 3920 2160 2273 2281 2287 +hsync -vsync
Last edited by progandy (2021-11-21 21:24:19)
| alias CUTF='LANG=en_XX.UTF-8@POSIX ' |
Offline
Please identify the output (vendor/model) [...]
GPU: PowerColor Radeon RX 550 Red Dragon V3, 2GB GDDR5, DVI, HDMI, DP (AXRX 550 2GBD5-DHA/OC)
Screen: Gigabyte Aorus FV43U
[...] post your xorg log,
4k/144 is not possible with this graphics card.
Display Stream Compression is not working on Linux?
4k/120 created with cvt12:
$ cvt12 3840 2160 120 -b # 3840x2160 @ 120.000 Hz Reduced Blank (CVT) field rate 120.000 Hz; hsync: 274.440 kHz; pclk: 1075.80 MHz Modeline "3840x2160_120.00_rb2" 1075.80 3840 3848 3880 3920 2160 2273 2281 2287 +hsync -vsync
[sapiens]$ xrandr --newmode "3840x2160_120.00_rb2" 1075.80 3840 3848 3880 3920 2160 2273 2281 2287 +hsync -vsync
[sapiens]$ xrandr --addmode DisplayPort-0 3840x2160_120.00_rb2
[sapiens]$ xrandr -v --output DisplayPort-0 --mode 3840x2160_120.00_rb2
xrandr program version 1.5.1
xrandr: Configure crtc 0 failed
Last edited by Sapiens (2023-01-07 16:50:56)
Offline
Display Stream Compression is not working on Linux?
Right, that exists as well. As far as I know, AMD RX 550 would be too old for that, though. Only Navi and newer have it I think.
Last edited by progandy (2021-11-21 22:56:41)
| alias CUTF='LANG=en_XX.UTF-8@POSIX ' |
Offline
Was added in 2019 https://lists.freedesktop.org/archives/ … 38759.html - but your GPU HW doesn't support it.
The monitor EDID reports the resolutions, but the driver filters them and apparently even on reduced blanking the 120Hz pclk is too high.
You can try https://wiki.archlinux.org/title/Variable_refresh_rate - the monitor supports it.
Offline
The missing DSC is unfortunate. Still I made some progress. I was able to create a custom resolution with 4K/110Hz that I was able to apply! At least that is working for now and I should be able to live with it until the GPU prices might come down and I can buy a GPU that is either HDMI2.1 or DSC capable. I will receive another DP cable tomorrow and see if that changes anything. So thank you both for helping!
I have an additional question though. When I boot the computer I land in the terminal since I start my I3 desktop environment with the `startx`-command. However after the grub menu the display stays completely black. I have to enter my login credentials and run startx blindly. When I3 starts the screen starts to display again! Is there anything I can do to make it display the console properly?
Last edited by Sapiens (2021-11-22 17:57:59)
Offline
Offline
Here is a customized 4K/120Hz you could try. The calculator I linked shows it as utilizing 99% of DP HBR3. (I shortened the vsync by 10 pixels, no idea if that will work for you)
Modeline "3840x2160_120.00_custom" 1071.101 3840 3848 3880 3920 2160 2263 2271 2277 +hsync -vsync
Last edited by progandy (2021-11-22 18:48:12)
| alias CUTF='LANG=en_XX.UTF-8@POSIX ' |
Offline
This makes it worse. Not only does the screen turn off after Grub, now I am not even seeing the decryption password promt.
Here is a customized 4K/120Hz you could try. The calculator I linked shows it as utilizing 99% of DP HBR3. (I shortened the vsync by 10 pixels, no idea if that will work for you)
Modeline "3840x2160_120.00_custom" 1071.101 3840 3848 3880 3920 2160 2263 2271 2277 +hsync -vsync
I can apply this mode! What does it mean that you shortened the vsync by10 pixels? I'm not sure what the implications are.
Last edited by Sapiens (2021-11-22 19:03:17)
Offline
I can apply this mode! What does it mean that you shortened the vsync by10 pixels? I'm not sure what the implications are.
That shortens the time used to send the "vertical blanking" signal and reduces the bandwidth consumed by it. I was a bit more aggressive than the "reduced blanking v2" as defined by VESA. If you monitor likes the signal, then there should be no problem at all.
https://en.wikipedia.org/wiki/Coordinat … d_blanking
For your invisible boot, maybe try to force a lower resolution during boot: https://wiki.archlinux.org/title/Kernel … cing_modes or try to force your new modeline with a custom edid: https://github.com/akatrevorjay/edid-generator
Last edited by progandy (2021-11-22 19:25:02)
| alias CUTF='LANG=en_XX.UTF-8@POSIX ' |
Offline
For your invisible boot, maybe try to force a lower resolution during boot: https://wiki.archlinux.org/title/Kernel … cing_modes
Forcing the resolution to FullHD@60Hz via kernel parameter worked and I am now able to see the console. Thank you, I will mark the thread as solved.
By the way, I also received a new high quality display port cable and the higher refresh rates are still unavailable without manually setting them.
Offline
The AMD RX 550 has "only" DP 1.4 support - using a DP 2.0 cable or one with golden plugs (sigh) won't change that.
The custom modelines you inject are not announced by the monitor EDID (what's not a surprise and normal and not a bug) and the more demanding ones that are announced, are filtered by the GPU because "can't do that, sorry".
Offline
Okay I get it.
Last edited by Sapiens (2023-01-07 16:52:22)
Offline
Like with anything in life there're good ones and bad ones, but again: this has nothing to do with the cable. The limiting factor is your GPU.
Offline