After dual booting Win 10/Ubuntu 14, Windows displays at 1366 x 768 with 10 display modes available.
Ubuntu has no options other than a "built-in" 800 x 600 low res output. The driver is the latest available for the AMD Radeon R6. This is for an HP Pavilion Notebook.
Research (mostly about nvidia cards) suggests use of xrandr
and cvt
commands in terminal which I've attempted without joy with a file attached containing outputs from various commands.
Notably,"size of gamma" and the name of the video device (ie, VGA) can't be found by xrandr
.
What can be tried to access and use a resolution of 1368x768?
What is "gamma" and why can't xrandr find it?
Here is further information including commands/outputs.
Computer: an HP Pavilion Laptop 64bit dual-booted Windows 10/Ubuntu 14.04 LTS. Graphics card: AMD Radeon R6, chip: Ox9874 Driver:AMD/ATI display driver wrapper from xserver-xorg-video-ati(open source, tested)--recommended.
OUTPUT from $>sudo lshw -C video
:
*-display UNCLAIMED description: VGA compatible controller product: Advanced Micro Devices, Inc. [AMD/ATI] vendor: Advanced Micro Devices, Inc. [AMD/ATI] physical id: 1 bus info: pci@0000:00:01.0 version: c5 width: 64 bits clock: 33MHz capabilities: pm pciexpress msi vga_controller bus_master cap_list configuration: latency=0 resources: memory:e0000000-efffffff memory:f0000000-f07fffff ioport:f000(size=256) memory:ff700000-ff73ffff memory:ff740000-ff75ffff
OUTPUT from $>xrandr
:
xrandr: Failed to get size of gamma for output default Screen 0: minimum 800 x 600, current 800 x 600, maximum 800 x 600 default connected primary 800x600+0+0 0mm x 0mm 800x600 75.0*
OUTPUT using cvt
with known max resolution from WIN 10 where 10 possible display modes exist....
~$> cvt 1366 768 60" # 1368x768 59.88 Hz (CVT) hsync: 47.79 kHz; pclk: 85.25 MHz Modeline "1368x768_60.00" 85.25 1368 1440 1576 1784 768 771 781 798 -hsync +vsync
~$ lspci| grep VGA 00:01.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Device 9874 (rev c5)
After attempting to add a newmode to xrandr and testing this output occurs;
~$ xrandr --newmode "1368x768_60.00" 85.25 1368 1440 1576 1784 768 771 781 798 -hsync +vsync xrandr: Failed to get size of gamma for output default 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: 16 (RRCreateMode) Serial number of failed request: 19 Current serial number in output stream: 19
~$ xrandr xrandr: Failed to get size of gamma for output default Screen 0: minimum 800 x 600, current 800 x 600, maximum 800 x 600 default connected primary 800x600+0+0 0mm x 0mm 800x600 75.0* 1368x768_60.00 (0x233) 85.2MHz h: width 1368 start 1440 end 1576 total 1784 skew 0 clock 47.8KHz v: height 768 start 771 end 781 total 798 clock 59.9Hz
When attempting to use >xrandr
to --addmode
these error messages occur:
xrandr --addmode default 1366x768_60.00 xrandr: Failed to get size of gamma for output default xrandr: cannot find mode "1366x768_60.00"
additional attempt to get xrandr
to accept a newmode and the resultant output:
~$ xrandr --newmode "1368x768_60.00" 85.25 1368 1440 1576 1784 768 771 781 798 -hsync +vsync xrandr: Failed to get size of gamma for output default 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: 16 (RRCreateMode) Serial number of failed request: 19 Current serial number in output stream: 19