I'm on a Dell Precision 7520 running Linux Mint 18.2 64-bit with Cinnamon. This machine has both an Intel integrated graphics provider, as well as an NVIDIA Quadro M1200 Mobile. I'm can't get a clear answer as to whether or not it has NVIDIA Optimus, but the BIOS has some sort of Graphics Switching option available. I'm using the nvidia-387 graphics drivers, and have nvidia-settings and nvidia-prime installed, but not bumblebee.
Here is my specific issue: when I have graphics switching enabled, I can dock my machine at my workstation and display through HDMI or Display Port to my external monitors with ease. However, if I try to output with VGA, the port isn't even available (xrandr has no VGA listed, despite lspci listing two VGA controllers, one for each graphics provider).
Here are some outputs:
So my question is: Is there a way to allow my machine to output through VGA? If not, why? If so, how?
I should also mention that if I disable graphics switching in the BIOS, I can display through VGA, but it seems to work very poorly (it's almost unusable), and also renders the laptop incapable of displaying through Display Port to my workstation monitors, though I'm not sure why. Perhaps the solution exists in this direction?
Apologies if I forgot to mention something important; I'm a little out of my depth here, to be honest. Thank you to everyone!