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smiley8088

Member

Registered: 2015-07-06

Posts: 2

xrandr: multi-monitor, aspect ratio and resolution problem

Hi, I cannot set the correct resolution and aspect ratio for my multi-monitor setup when using the proprietary nvidia driver.  My graphics card is a Gigabyte Geforce GT730.

I have two monitors with slightly different aspect ratios. A 1680x1050 connected to VGA-0 and a 1920x1080 connected to HDMI-0. I want the same thing displayed on both monitors, at the correct aspect ratio. I don't care if the larger display is pillarboxed or windowboxed, though pillarboxed is nicer.

Using the open source nouveau driver, I can get what I want very easily:

 
$ xrandr --output HDMI-0 --same-as VGA-0
$ xrandr --output HDMI-0 --set "scaling mode" "Full aspect"

However, using the proprietary nvidia driver (which I want to use for other reasons), this is what happens:

 
$ xrandr --output HDMI-0 --set "scaling mode" "Full aspect"
X Error of failed request:  BadName (named color or font does not exist)
  Major opcode of failed request:  140 (RANDR)
  Minor opcode of failed request:  11 (RRQueryOutputProperty)
  Serial number of failed request:  37
  Current serial number in output stream:  37

Checking xrandr --prop gives me this:

$ xrandr --prop
HDMI-0 connected primary 1866x1050+1+0 (normal left inverted right x axis y axis) 510mm x 290mm panning 1867x1050+1+0 tracking 1867x1050+0+0 border 0/0/0/0
        EDID: 
                00ffffffffffff0009d1367b45540000
                0519010380331d782ee595a656529d27
                105054a56b80818081c08100a9c0b300
                d1c001010101023a801871382d40582c
                4500fd1e1100001e000000ff00583146
                30303630313031510a20000000fd0032
                4c1e5311000a202020202020000000fc
                0042656e5120565a323335300a20007b
        BorderDimensions: 4 
                supported: 4
        Border: 0 0 0 0 
                range: (0, 65535)
        SignalFormat: TMDS 
                supported: TMDS
        ConnectorType: HDMI 
        ConnectorNumber: 1 
        _ConnectorLocation: 1 
   1920x1080     60.00 +
   1680x1050     59.95* 
   1600x900      60.00  
   1280x1024     75.02    60.02  
   1280x800      59.81  
   1280x720      60.00  
   1024x768      75.03    60.00  
   800x600       75.00    60.32  
   640x480       75.00    59.94  

Unlike the output when using nouveau, this makes no mention of the "scaling mode" property.

So I try something more creative:

$ xrandr --output HDMI-0 --scale `echo 1/0.9 | bc -l`x1
$ xrandr
HDMI-0 connected primary 1867x1050+0+0 (normal left inverted right x axis y axis) 510mm x 290mm

It has scaled the output to the correct aspect ratio, but it has also expanded the desktop! Trying the same thing with a transform seems to have a similar result:

$ xrandr --output HDMI-0 --mode 1680x1050 --transform 1.111,0,0,0,1,0,0,0,1
HDMI-0 connected primary 1866x1050+1+0 (normal left inverted right x axis y axis) 510mm x 290mm panning 1867x1050+1+0 tracking 1867x1050+0+0 border 0/0/0/0

It has added these panning/tracking parameters, so I though maybe I could solve the problem by setting those to proper values:

$ xrandr --output HDMI-0 --panning 1680x1050/1680x1050
X Error of failed request:  BadMatch (invalid parameter attributes)
  Major opcode of failed request:  140 (RANDR)
  Minor opcode of failed request:  29 (RRSetPanning)
  Serial number of failed request:  37
  Current serial number in output stream:  37

No such luck. I ran the same command without the extra /1680x1050 for the tracking, and it failed in the same manner. However, both commands work when run for VGA-0 instead, so they are being understood correctly.

Does anyone know what else I might try? For window manager I'm using Openbox (no DE).

Please let me know if any more information is needed.