I'm running Ubuntu 19.10, and I was following the instructions in the answer about how to add a higher resolution mode using xrandr, and I ran into a problem. What I need is to be able to use an external monitor with the 5120 by 2160 resolution. So I first ran cvt:
$ cvt 5120 2160
# 5120x2160 59.99 Hz (CVT) hsync: 134.19 kHz; pclk: 949.00 MHz
Modeline "5120x2160_60.00" 949.00 5120 5536 6096 7072 2160 2163 2173 2237 -hsync +vsync
Having that, I created the mode using xrandr:
$ sudo xrandr --newmode "5120x2160_60.00" 949.00 5120 5536 6096 7072 2160 2163 2173 2237 -hsync +vsync
After that I added the mode to the connected display:
$ sudo xrandr --addmode DP-1-1 "5120x2160_60.00"
It appeared in the output of xrandr:
$ xrandr
Screen 0: minimum 8 x 8, current 3440 x 2592, maximum 32767 x 32767
eDP-1-1 connected 2048x1152+720+1440 (normal left inverted right x axis y axis) 344mm x 194mm
3840x2160 60.00 + 59.98 59.97
... SNIP ....
DP-1-1 connected primary 3440x1440+0+0 (normal left inverted right x axis y axis) 800mm x 330mm
3440x1440 59.97*+ 59.96 49.99
... SNIP ...
5120x2160_60.00 59.99 <-- THIS IS THE MODE I NEED
DP-1-2 connected (normal left inverted right x axis y axis)
2560x2160 59.66
640x480 59.94
DP-1-3 disconnected (normal left inverted right x axis y axis)
5120x2160_60.00 (0x290) 949.000MHz -HSync +VSync
h: width 5120 start 5536 end 6096 total 7072 skew 0 clock 134.19KHz
v: height 2160 start 2163 end 2173 total 2237 clock 59.99Hz
After that I'm trying to switch the monitor to that mode using Ubuntu's settings dialog, but I only get a black screen on the external monitor. What's funny is that I can see the mouse cursor on it, and it moves, but everything else is black, changing the mode back doesn't help - only turning the monitor off and on again gives me the image back. What should I do next?
Here's the output I get from lshw:
$ sudo lshw -C display
*-display
description: 3D controller
product: NVIDIA Corporation
vendor: NVIDIA Corporation
physical id: 0
bus info: pci@0000:01:00.0
version: a1
width: 64 bits
clock: 33MHz
capabilities: pm msi pciexpress bus_master cap_list rom
configuration: driver=nvidia latency=0
resources: irq:182 memory:ec000000-ecffffff memory:c0000000-cfffffff memory:d0000000-d1ffffff ioport:3000(size=128) memory:ed000000-ed07ffff
*-display
description: VGA compatible controller
product: UHD Graphics 630 (Mobile)
vendor: Intel Corporation
physical id: 2
bus info: pci@0000:00:02.0
version: 00
width: 64 bits
clock: 33MHz
capabilities: pciexpress msi pm vga_controller bus_master cap_list rom
configuration: driver=i915 latency=0
resources: irq:151 memory:eb000000-ebffffff memory:80000000-8fffffff ioport:4000(size=64) memory:c0000-dffff
