Ubuntu – Unable to change the refresh rate to 60hz with xrandr

12.04nvidiaxorgxrandr

My monitor supports 1920×1080 @ 60hz (LG W2486L) and graphic card (GeForce 9400 GT)
using Ubuntu 12.04.

When I type xrandr -q I get this:

xrandr -q
xrandr: Failed to get size of gamma for output default
Screen 0: minimum 1920 x 1080, current 1920 x 1080, maximum 1920 x 1080
default connected 1920x1080+0+0 0mm x 0mm
1920x1080      50.0* 
1920x1080_59.90   59.9  
1920x1080_60.00   60.0  

Right now the refresh rate is on 50 and hurt my eyes real bad.
So I'm trying to change it to 60hz:

xrandr --output default --mode 1920x1080_60.00
xrandr: Failed to get size of gamma for output default

What I can do? I tried

gtf 1920 1080 60.0

# 1920x1080 @ 60.00 Hz (GTF) hsync: 67.08 kHz; pclk: 172.80 MHz
Modeline "1920x1080_60.00"  172.80  1920 2040 2248 2576  1080 1081 1084 1118  -HSync +Vsync

xrandr --newmode "1920x1080_60.00"  172.51  1920 2040 2248 2576  1080 1081 1084 1118  -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:  153 (RANDR)
  Minor opcode of failed request:  16 (RRCreateMode)
  Serial number of failed request:  19
  Current serial number in output stream:  19

xrandr --output default --mode 1920x1080_60.00
xrandr: Failed to get size of gamma for output default

Someone have the solution for this? I can't work on the PC like that, 50Hz is very low and can't look at the screen more than 5 mins.

Thank you!

Best Answer

Your xrandr -q output shows that you have 1920x1080_59.90 resolution available

You can use this to set the new resolution

xrandr --output default --mode 1920x1080_59.90 

Also, if you are creating newmode using

xrandr --newmode "1920x1080_59.90"  172.51  1920 2040 2248 2576  1080 1081 1084 1118  -HSync +Vsync

You also need to add this mode using

xrandr --addmode default 1920x1080_59.90

And then set the new resolution using

xrandr --output default --mode 1920x1080_59.90