On Wednesday 08 February 2017 21.56:32 deloptes wrote:
> Thierry de Coulon wrote:
> > My problem is this: while I have the screen resolution setup to 1920x1080
> > (and trinity desktop looks OK for this resolution), the monitor (which is
> > accessed from HDMI through an HDMI to VGA converter because I use a KVM
> > that needs VGA connectors) was initially "seen" as 1024x768.
>
> It is interesting to know what is the output of xrandr
>
> I have/had similar issues with my notebook(s) and external monitor.
> Natively eDP1 supports  1366x768, while monitor does 1920x1080.
>
> So switching on and of the one and the other messed up from time to time
> the modesettings and I end up with unusable resolution. The external would
> refuse to accept 1920x1080. It improved recently with later 4.9 kernel and
> I did not test extensively.
> One option was to configure monitors in xorg.conf with their mod lines. I
> did this on the older notebook
> I however use now xrandr --scale as X tends to pick up the lowest common
> and it can not support different resolutions or whatever. So I put the
> bigger one to  1920x1080 and scale eDP1., which gives acceptable output.
>
> I have read of similar issues with KVM.
>
> regards
>

That's what I get:

Screen 0: minimum 320 x 200, current 1920 x 1080, maximum 8192 x 8192
DP1 disconnected (normal left inverted right x axis y axis)
HDMI1 connected 1920x1080+0+0 (normal left inverted right x axis y axis) 256mm 
x 192mm
   1024x768      60.00 +
   1920x1080     60.00*   59.94  
   1280x1024     85.02    60.02  
   1440x900      74.98    59.90  
   1280x960      60.00  
   1360x768      60.02  
   1280x800      59.91  
   1280x720     119.99    60.00    59.94  
   720x480       60.00    59.94  

To me it seems the chipset by itself can do a lot of resolutions. I am new to 
HDMI (I actually don't use it anwhere as I have no monitor with such a 
connector). So I can't test what would happen if I had a direct connection to 
the monitor.

I could imagine that the chain HDMI - HDMI to VGA (cheap chinese thing, by the 
way) - KVM switch - monitor is too much for a system that desperately tries 
to identify the monitor by itself. In the old time I would have been asked 
what my screen was...

Thierry