Something overwrites Xorg.conf file on reboot

[ivo2296]

Hello, I'm trying use VGA monitor as primary on my laptop Lenovo G710, but when I switch to Nvidia PRIME i hit a wall:
1. No matter of my saved configuration every time I reboot or log out xorg.conf in /etc/X11/ is overwritten and i lose the settings without even get the chance to see them.
2. Also in nvidia x server i don't see two monitors but instead it shows one(a huge one) with almost combined resolution of both(display+VGA monitor) and that results a very small display font(like 5 pt) on all system menus.
I have spent a week reading solutions, full documentation of nvidia installation guide, at least 30 fresh OS installations with all linux mint latest 17.2 distros and ubuntu ones, even the latest nvidia drivers, linux stable kernel and newest Intel microcodes.
The problem could be in the xserver not supporting yet such configuration, especially laptops with Optimus technology in which this can't be turned off in the BIOS(there in Lenovo G710 i can turn off only the nvidia graphic card).

My goal is to use Linux with Nvidia Cuda for video and graphical rendering, that's why i need the external VGA monitor.
Till then i have to use Windows OS - sadly.

Best regards!

[Greg (cebif)]

I have the same but only one monitor on two different desktop computers. Nvidia settings are back to default after reboot or re login. I am seeing this on Mint 18.2 Sonya Cinnamon. I have seen this since first trying Mint 16.