RPi2 video problem in Ubuntu MATE

Support & Help Requests Raspberry Pi
1

I’m having some problems getting video to work in Ubuntu MATE with a RPi2 on a 1280x1024 monitor.

A brand new install of Ubuntu MATE (v15.10) is rendering only onto a portion of the screen, leaving a large black vertical line.

[Album] RPi2

The RPi2 and the monitor both work just fine - OSMC renders perfectly fine in the correct resolution. The monitor is hooked up with a DVI cable through a DVI-HDMI adapter, if it matters.

I’ve gone through all of the graphics related config.txt suggestions and troubleshooting I could Google-up:

  • un-commented disable_overscan=1
  • manually set monitor’s optimal resolution with hdmi_mode=35 (1280x1024@60Hz) and hdmi_group=2

What’s confusing me is that Ubuntu seems to think it’s outputting 1280x1024 - according to xrandr -q and the monitor preferences - but the monitor clearly disagrees, as it’s displaying the “Use optimal resolution” warning message in the menu.

What am I missing?

2

Have you tried resetting your monitor?. :smiley:

3

Are you refereeing to resetting the monitor to default factory settings in the OSD menu? If that, then yes, but that doesn’t really do anything - it only resets the color presets and brightness levels.

Still having this problem - any ideas?

4

I have the same issue, but my monitor is 1680x1050 and xrandr matches. The monitor information tab on OSD reports 1952x1050 @ 60 hz.
I am using a HDMI to DVI cable.
Any ideas?

5

Do you both have higher or lower res settings in the Ubuntu Display Manager and can you raise or lower that setting?. :smiley:

6

@nexprime @mjf55 Have you tried using the command cvt?

This command calculates VESA Coordinated Video Timing modelines which can then be used to create new modes using xrandr.

For example, the command -

cvt 1280 1024

gives the output -

1280x1024 59.89 Hz (CVT 1.31M4) hsync: 63.67 kHz; pclk: 109.00 MHz
Modeline "1280x1024_60.00" 109.00 1280 1368 1496 1712 1024 1027 1034 1063 -hsync +vsync

You can now create a new mode using the information above -

xrandr --newmode "1280x1024_60.00"  109.00  1280 1368 1496 1712  1024 1027 1034 1063 -hsync +vsync