I recently installed Linux Mint 18 on my ThinkPad T460p. Having a dual monitor set-up with a internal HiDPI display and a full HD external display connected via Display Port, I tried to adjust the scaling factor of the internal one while leaving the external one untouched.For that matter, I first ran xrandr -q to check the respective ports, and, subsequently,xrandr --output eDP-1-1 --auto --output DP-1-2-8 --auto --scale 2x2 --right-of eDP-1-1As a result, the following error messages were printed:X Error of failed request:  BadValue (integer parameter out of range for operation)Major opcode of failed request:  140 (RANDR)Minor opcode of failed request:  26 (RRSetCrtcTransform)Value in failed request:  0x40Serial number of failed request:  47Current serial number in output stream:  48The same was printed when runningxrandr --output eDP-1-1 --auto --output DP-1-2-8 --auto --panning 3840x2400+2560+0 --scale 2.0x2.0 --right-of eDP-1-1To me, these error messages are entirely cryptic. The lack of information on the opcodes makes this a difficult, almost undebugable problem for me. For the commands, I followed the instructions given on ArchWiki.What intuitively might be of interest to that problem is that instead of running nouveau, I run the proprietary nvidia (nvidia-367, to be precise) drivers to power my GeForce 940MX.  Thanks for your input.
Scaling only HiDPI display with xrandr in dual monitor set-up
linux mint;xrandr;displayport