I have an HP Touchsmart laptop that has a 3rd-gen Intel Core i3-3120M with integrated Intel HD Graphics 4000. I'd like to be able to use my internal display, an HDMI display, and a VGA display (I have all the ports necessary), and I'd like to extend the desktop to each. According to Intel's website, that specific combination of displays is supported by Intel HD Graphics 4000 on any 3rd-gen Core chip. However, I can only use two displays at a time. When I try to connect the thrid, I get an error saying "could not set the configuration for CRTC 64." I've read that Xinerama can be used to run 3 displays, but it requires me to edit my xorg.conf file, which I can't find. Also, I can't get more than 2 displays running on Windows 8.1 either. Is there a way I can run 3 displays, or did Intel lie to me?
41 Answer
You should look for xrandr and arandr (xrandr gui). This is the best solution I found to set up freely multiple screens under ubuntu
Arandr let you configure screen :
- Status (Active / Inactive)
- Position (free positioning)
- Orientation (normal, right, inverted or left)
- Resolution
Note to intel graphics owners : if you want to use more than 2 screens, be aware to have two configurations set for all your screens. (ex : Screens 1/2&3 : 1280x1024 60.0 and screens 4/5&6 : 1280x1024 75.0)
But this type of config is available through DisplayPort only for most of configs
Intel only support 2 PLL (wikipedia) this why only two configuration sets. See Adam Jackson's comment here.
