NoVNC Maximum resolution | ~2800x2000 pixels

Anotheruser

Member
Sep 21, 2022
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So i have been experimenting with higher resolution vms over the past few days and noticed that there seems to be a limit on the resolution that novnc can transmit.
Basically everything above around 2800 pixels height and 2000 pixels width gets just cut of in no vnc (but the vm itself still renders the full resolution, it is just not transmitted in novnc (you can actually see that on the preview view of paint in the taskbar in the image thats rendered in the correct 16:9 ratio)
This causes vms that are set to 3840x2160 to be cut of in a weird aspect ration close to 4:3. (see image)
This happens in windows as well as linux vms and it doesnt matter if virtio-gpu or standard vga is used.
I also tried taking screenshots inside the vm and they have the correct resolution with nothing cut of all the way up to 5120x2160, so this should mean that the vm renders correctly and its a novnc problem.
2560x1440 resolution is the last one that displays correctly everything higher than that is cut of on the no vnc stream.
I tried different novnc settings but always same result, including when locale scaling is activated, also the bottom is also slightly cut of by vnc at 2160p as you can see in the image (the time is partially cut of)

Is this a known problem?
How to fix that?
 

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So i have been experimenting with higher resolution vms over the past few days and noticed that there seems to be a limit on the resolution that novnc can transmit.
Basically everything above around 2800 pixels height and 2000 pixels width gets just cut of in no vnc (but the vm itself still renders the full resolution, it is just not transmitted in novnc (you can actually see that on the preview view of paint in the taskbar in the image thats rendered in the correct 16:9 ratio)
This causes vms that are set to 3840x2160 to be cut of in a weird aspect ration close to 4:3. (see image)
This happens in windows as well as linux vms and it doesnt matter if virtio-gpu or standard vga is used.
I also tried taking screenshots inside the vm and they have the correct resolution with nothing cut of all the way up to 5120x2160, so this should mean that the vm renders correctly and its a novnc problem.
2560x1440 resolution is the last one that displays correctly everything higher than that is cut of on the no vnc stream.
I tried different novnc settings but always same result, including when locale scaling is activated, also the bottom is also slightly cut of by vnc at 2160p as you can see in the image (the time is partially cut of)

Is this a known problem?
How to fix that?
I also have this issue and found this page. It would be good to see any resolution or workaround.