I want to be able to use the DisplayPort on my laptop hooked up to a [DP to (2) DVI] adapter to drive two external displays (both using DVI).
This is the adapter I have: http://www.startech.com/AV/Splitters/DisplayPort/DisplayPort-to-Dual-DVI-Multi-Monitor-Adapter-Male-to-Female-DP-to-2x-DVI-3840x1200~SP122DP2DVI
I am currently able to use the little Startech box to passthrough only one DVI output, but when I hook up a second one it does not work (Ubuntu will not detect any additional displays).
EDIT - I am able to get the adapter to show duplicated display data on both DVI outputs now... but I want to expand desktop rather than duplicate - Amazingly, I am able to change the resolution on what the driver believes to be 1 display to a resolution of 1920x1080 x2 = 3840x1080 which does technically give me display space expanded to both monitors BUT it's weird and the system things it's one huge monitor. Maybe there's a way to logically divide one display into more display areas? My current situation looks kind of like this issue which unfortunately was never really solved unless I want to add a source change myself:
https://unix.stackexchange.com/questions/37739/split-a-physical-x-display-into-two-virtual-displays
If I look at amdcccle (amd catalyst control center) and view the display info for the monitors hooked up though the displayPort, it mysteriously says that MST is not available.
Support wise - everything I have seems to indicate that support is present. ATI has Eyefinity support on the graphics chip. DisplayPort is new enough to have Multi-monitor support. StarTech claims that the adapter supports Linux (this may be an empty notion of course).
Current setup (not working):
HP Elitebook 8570w + XUbuntu 14.04 x64 LTS + DisplayPort using MST (multi streaming support) + Startech.com SP122DP2DVI (adapter with DisplayPort to 2 DVI ports)
Also using 2 ACER 1080p monitors that are DVI compatible.
Notes -
Graphics stuff on HP Elitebook is ATI/AMD Chelsea XT GL [Firepro M4000] with Eyefinity support through the DisplayPort connector. Currently running the proprietary driver from ATI (fglrx) as listed in the XUbuntu system. An open source driver is available, but I figure I'll get less success that way (xserver-xorg-video-ati).