I have a PC with 2x AMD Radeon R5 230 graphics cards, one with 2x 1920×1080 screens plugged (HTMI and DVI) and another with 1x 1920×1080 screen (HDMI).
I have the two screens in the first graphics card rotated to portrait mode and the screen on the second graphics card in landscape mode.
I configured the desktop using the unity UI tools (System Settings -> Screen Display) and got the screens set up as I want them, however when I set the second screen on graphics card 1 to rotate, both portrait screens get their resolution cut by about 400 pixels.
Looking at xrandr -q I see the following:
Screen 0: minimum 320 x 200, current 4920 x 1515, maximum 16384 x 16384
HDMI-0 connected 1080x1920+0+12 left (normal left inverted right x axis y axis) 531mm x 299mm
1920x1080 60.00*+ 50.00 59.94 24.00 23.98
1920x1080i 60.00 50.00 50.00 59.94
1600x1200 60.00
1680x1050 59.88
1600x900 60.00
1280x1024 75.02 60.02
1440x900 74.98 59.90
1280x960 60.00
1152x864 75.00
1280x720 60.00 50.00 59.94
1024x768 75.08 70.07 60.00
832x624 74.55
800x600 72.19 75.00 60.32 56.25
720x576 50.00
720x576i 50.00
720x480 60.00 59.94
720x480i 60.00 59.94
640x480 75.00 72.81 66.67 60.00 59.94
720x400 70.08
DVI-0 connected 1080x1920+3000+0 left (normal left inverted right x axis y axis) 531mm x 299mm
1920x1080 60.00*+ 144.00 119.98 109.95 99.93 59.94
1600x1200 60.00
1680x1050 59.88
1280x1024 120.00 100.00 75.02 60.02
1440x900 59.90
1280x960 60.00
1152x864 75.00
1024x768 119.99 99.97 75.08 70.07 60.00
832x624 74.55
800x600 72.19 75.00 60.32 56.25
640x480 75.00 72.81 66.67 60.00 59.94
720x400 70.08
VGA-0 disconnected (normal left inverted right x axis y axis)
HDMI-1-1 connected primary 1920x1080+1080+435 531mm x 299mm
1920x1080 60.00*+ 50.00 59.94 24.00 23.98
1920x1080i 60.00 50.00 50.00 59.94
1600x1200 60.00
1680x1050 59.88
1600x900 60.00
1280x1024 75.02 60.02
1440x900 74.98 59.90
1280x960 60.00
1152x864 75.00
1280x720 60.00 50.00 59.94
1024x768 75.08 70.07 60.00
832x624 74.55
800x600 72.19 75.00 60.32 56.25
720x576 50.00
720x576i 50.00
720x480 60.00 59.94
720x480i 60.00 59.94
640x480 75.00 72.81 66.67 60.00 59.94
720x400 70.08
DVI-1-1 disconnected
VGA-1-1 disconnected
As you can see from the output above, even though all screens are set to their highest resolution, the size of Screen 0 is set to 4920×1515 instead of 4920×1920. I have been trying to change that screen size without success. What I tried:
preichert@2015-PC-19:~/.config$ cvt 4920 1920 60
# 4920x1920 59.97 Hz (CVT) hsync: 119.28 kHz; pclk: 808.25 MHz
Modeline "4920x1920_60.00" 808.25 4920 5312 5848 6776 1920 1923 1933 1989 -hsync +vsync
preichert@2015-PC-19:~/.config$ xrandr --newmode "4920x1920_60.00" 808.25 4920 5312 5848 6776 1920 1923 1933 1989 -hsync +vsync
preichert@2015-PC-19:~/.config$ xrandr --screen 0 --size 4920x1920
Size 4920x1920 not found in available modes
I haven't tried yet to create a custom xorg.conf file as I see that as a last resort thing and I don't know how to configure my two graphics cards on that. This is what they look like:
preichert@2015-PC-19:~/.config$ lspci
...
01:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Caicos [Radeon HD 6450/7450/8450 / R5 230 OEM]
01:00.1 Audio device: Advanced Micro Devices, Inc. [AMD/ATI] Caicos HDMI Audio [Radeon HD 6400 Series]
02:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Caicos [Radeon HD 6450/7450/8450 / R5 230 OEM]
02:00.1 Audio device: Advanced Micro Devices, Inc. [AMD/ATI] Caicos HDMI Audio [Radeon HD 6400 Series]
...
And:
preichert@2015-PC-19:/usr/share/X11/xorg.conf.d$ xrandr --listproviders
Providers: number : 3
Provider 0: id: 0xa6 cap: 0x9, Source Output, Sink Offload crtcs: 4 outputs: 3 associated providers: 2 name:radeon
Provider 1: id: 0x46 cap: 0x6, Sink Output, Source Offload crtcs: 4 outputs: 3 associated providers: 2 name:radeon
Provider 2: id: 0x46 cap: 0x6, Sink Output, Source Offload crtcs: 4 outputs: 3 associated providers: 2 name:radeon
Best Answer