further discussion on video resolution

[Strak8]

Good evening, I can not set the resolution on HVM's in Qubes 3.2.
Beyond the fact that I have a second GPU Radeon on the Dell laptop which I assume can not only use for Hvm in gpu/pci passthrough mode, considering it a utopia. (Trying to devote the second GPU in vm-manager/vm-setting/device get a machine crash)
I made many tests, I do not seek prompt solution.
For now I only have 2 HVM, a Windows 10 machine and a debian based distro.
On Windows 10 I can choose different resolutions, even the largest, but 1366x768 is not present.
On debian within only with the setting grub deprecated vga=792 to boot. Changes in terminal with Xandr give it full of artifacts screen, making it unusable (ctrl+F1 does not work). Commands vbeinfo and vbetest in grub console cause the crash.
On debian based I had ssh server install when I had the screen unusable. Although fortunately so far the login screen is always accessible, so I can set the test resolutions of another user, if it is unusable can easily reset the configuration.
I have read that there are still some problems, which might have already been fixed in version 4.0, and perhaps there is a great desire to operate the 3.2.
IMPORTANT:I do not seek the possibility of having the fullscreen, I would just have the windows of Hvm the desired resolution. I did not expect to have all these problems only to change resolution, and I am conscious of not being a super user in linux.
Maybe I could use VNC or similar software, but in addition to not be safe to customize the resolution should install the client in dom0, otherwise I would have another vm and therefore use of resources and opening firewall ports.
On Windows 10 only needed xen video drive that accepts the 1366x768 resolution
On Debian based disto I read that with xfce would solve the problems.

Thanks for your help.

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