Problem choosing resolution with xrandr command in Ubuntu

Hi Everybody.

I have a GTX 1050 Ti, OS Ubuntu 16.04 - 64 bits. My problem is, for an output of the Nvidia card (HDMI port), I can’t set a custom screen resolution with xrandr command. I only can set the resolutions provided by Nvidia by default.

However, for the integrated graphic card of the PC (Intel), I can set any custom resolution with xrandr.

I would like to know why this happens.
So, has anyone been able to set a custom resolution using a Nvidia card??

Thank you.

Robert.