What does it means "a bad EDID info" ? I don't understand.
I already have the package x11-xserver-utils, here is the output of xrandr command :
xrandr: Failed to get size of gamma for output default Screen 0: minimum 1024 x 768, current 1024 x 768, maximum 1024 x 768 default connected primary 1024x768+0+0 0mm x 0mm 1024x768 76.0*
