Hybrid graphics and display scaling

I’ve done extensive searching and have not managed to find a solution for this yet.

I have a Dell M3800 with muxless hybrid graphics, Intel and a K1100M. I’m running the latest 352 drivers. What I would like to do is run an external monitor which is 1920x1080 while the laptop screen is 3840x2160.

Scaling should do the trick using xrandr something like this

xrandr --output eDP-1-0 --auto --output HDMI-1-0 --mode 1920x1080 --fb 3840x2160 --scale 2x2

It fails with the following

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: 0x40
Serial number of failed request: 38
Current serial number in output stream: 39

This actually works with the noveau drivers except for scaling the mouse pointer.

Is it possible to offload the scaling to the Intel adapter? Or is it just going to be easier to get a 4k external monitor.

The other thing that doesn’t behave is the nvidia-settings program segfaults if you click detect displays. Is this because the nvidia card has no outputs and all the connectiobs are through the intel adapter?

I’m running Mint 17.2 with Cinnamon as it handles HiDPI scaling the best.

Any help would be appreciated.

Forgot the log

https://drive.google.com/file/d/0BxrvdHslveJNODRRb3hPTnlweWs/view?usp=sharing

Have you tried nvidia-settings ?