Can't enable 4k resolution on external display

I have a MSI GL-65 Leopard ms-16u8 notebook with Ubuntu 20.04.1 installed.
My notebook, according to the specification, has a 4K capable HDMI(version 1.4, 4K at 30Hz) port, Intel GPU and Nvidia GeForce GTX 1650.
I have LG 27UL500-W external display, which supports resolutions up to 4K(3840 x 2160) and is connected with a 4k capable HDMI cable.
My driver is nvidia-driver-460.

In Settings -> Displays I can’t enable 3840x2160 resolution for my external display(set at 30 hz), only resolutions up to 1920x1080 are available.

I tried all kinds of things like creating and adding a custom mode, which only gives me black screen when trying to enable it:

gtf 3840 2160 30
  3840x2160 @ 30.00 Hz (GTF) hsync: 65.91 kHz; pclk: 339.57 MHz
  Modeline "3840x2160_30.00" 339.57 3840 4080 4496 5152 2160 2161 2164 2197 -HSync +Vsync
xrandr --newmode "3840x2160_30.00" 339.57 3840 4080 4496 5152 2160 2161 2164 2197 -HSync +Vsync
xrandr --addmode HDMI-1-2 "3840x2160_30.00"
xrandr --output HDMI-1-2 --mode "3840x2160_30.00"

I have another laptop(Dell g3, Ubuntu 20.04) which immediately recognizes this monitor as 4K and allows setting 3840 x 2160 resolution(that’s how I know, that my HDMI cable is 4k capable).

My xrandr output:

Screen 0: minimum 320 x 200, current 3840 x 1080, maximum 16384 x 16384
eDP-1 connected 1920x1080+1920+0 (normal left inverted right x axis y axis) 344mm x 193mm
1920x1080 120.11*+ 59.97 59.96 59.93 48.08
1680x1050 84.94 74.89 69.88 59.95 59.88
1600x1024 60.17
1400x1050 85.00 74.76 70.00 59.98
1600x900 59.99 59.94 59.95 59.82
1280x1024 85.02 75.02 60.02
1440x900 59.89
1400x900 59.96 59.88
1280x960 85.00 60.00
1440x810 60.00 59.97
1368x768 59.88 59.85
1360x768 59.80 59.96
1280x800 59.99 59.97 59.81 59.91
1152x864 100.00 85.06 85.00 75.00 75.00 70.00 60.00
1280x720 60.00 59.99 59.86 59.74
1024x768 85.00 75.05 60.04 85.00 75.03 70.07 60.00
1024x768i 86.96
960x720 85.00 75.00 60.00
928x696 75.00 60.05
896x672 75.05 60.01
1024x576 59.95 59.96 59.90 59.82
960x600 59.93 60.00
832x624 74.55
960x540 59.96 59.99 59.63 59.82
800x600 85.00 75.00 70.00 65.00 60.00 85.14 72.19 75.00 60.32 56.25
840x525 85.02 74.96 69.88 60.01 59.88
864x486 59.92 59.57
800x512 60.17
700x525 85.08 74.76 70.06 59.98
800x450 59.95 59.82
640x512 85.02 75.02 60.02
720x450 59.89
700x450 59.96 59.88
640x480 85.09 60.00 85.01 72.81 75.00 59.94
720x405 59.51 58.99
720x400 85.04
684x384 59.88 59.85
680x384 59.80 59.96
640x400 59.88 59.98 85.08
576x432 100.11 85.15 85.09 75.00 75.00 70.00 60.06
640x360 59.86 59.83 59.84 59.32
640x350 85.08
512x384 85.00 75.03 70.07 60.00
512x384i 87.06
512x288 60.00 59.92
416x312 74.66
480x270 59.63 59.82
400x300 85.27 72.19 75.12 60.32 56.34
432x243 59.92 59.57
320x240 85.18 72.81 75.00 60.05
360x202 59.51 59.13
360x200 85.04
320x200 85.27
320x180 59.84 59.32
320x175 85.27
DP-1 disconnected (normal left inverted right x axis y axis)
HDMI-1 disconnected (normal left inverted right x axis y axis)
HDMI-2 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 600mm x 340mm
1920x1080 60.00 50.00 59.94 30.00* 24.00 29.97 23.98
1600x900 60.00
1280x1024 60.02
1280x800 59.91
1280x720 60.00 59.94
1024x768 60.00
800x600 60.32
720x576 50.00
720x480 60.00 59.94
640x480 60.00 59.94

It’s a bit odd that the notebook’s specs only talk of 4k@30Hz since both the 10th gen igpu and the gtx 1650 should support hdmi 2.0.
Please run nvidia-bug-report.sh as root and attach the resulting nvidia-bug-report.log.gz file to your post.

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For some reason, both the high level and low level versions of this notebook model support only HDMI 1.4. See, for example, “1x (4K @ 30Hz) HDMI” in “I/O Ports”:

I’ve attached the log file to this reply:
nvidia-bug-report.log.gz (319.2 KB)

All your external connectors are connected to the intel gpu which is an old 9.5 gen built into a 10th gen cpu thus only supports hdmi1.4. Despite supporting 300MHz pixelclock, the i915 driver seems to disable the 4k@30 mode (297MHz)
Taken from the monitor’s edid the correct modeline is:

Modeline "3840x2160_30.00" 297.0 3840 4016 4104 4400 2160 2168 2178 2250 +hsync -vsync

for HDMI-2
if that’s still rejected, you’ll have to open a bug report for the i915 driver at the kernel bugzilla.

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generix, you are gentleman and a scholar, almost a saint. Thank you for bringing me to the World Of 4K!