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I am planning to use Surface Pro 2 with a dock station as my main computer and I would like to connect two external monitors to it, but the dock station only contains a single DisplayPort socket. However, I see that DisplayPort 1.2 specification, approved in 2009, allows for daisy-chaining monitors through its Multi-Stream Transport feature.

How do I tell if I will be able to use two monitors in daisy-chain mode with my computer?

Nickolai Leschov
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    DisplayPort MST does not work in Linux yet, see my answer to Thinkpad w540 w/ Ultra Dock only one external monitor works – bain May 30 '14 at 23:42
  • @bain D'oh! Thanks for the information. Does this mean that solution with the external hub won't work either, unless we'll manage to install these work-in-progress patches? – Nickolai Leschov May 30 '14 at 23:46
  • Any form of MST is not supported yet. That includes DisplayPort MST hubs and daisy chained monitors. If you build the very latest git kernel source with David Airlie's patches it might work.. but I wouldn't recommend that for a regular user. – bain May 30 '14 at 23:51
  • I see. I don't feel myself entirely comfortable building the (development) kernel, either. I did build some software, but building gcc or kernel looks daunting. When and in which form, more appropriate for regular users, can we expect this support to appear? (ppa for 14.04?) – Nickolai Leschov May 31 '14 at 00:09
  • I would guess about 3 months until Linux 3.16. There is a lot of support for building custom kernels in Ubuntu; it as an opportunity to learn. The MST code is very recent and not well tested, so the more people who have real MST hardware and test it out, the better. You could wait for 3.16 and find that there is a bug specific to your hardware. – bain May 31 '14 at 09:47

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Update: As of July 8, 2014, DisplayPort MST support does not exist in any Linux kernel. David Airlie at Red Hat is working on it, and his work is being merged in Linux kernel 3.17. The upcoming Ubuntu 14.10 "Utopic Unicorn" will use 3.16, so DisplayPort MST support "out-of-the-box" is not expected on Ubuntu until 15.04 (yes, nearly a year from now). I will update this answer with instructions on installing the patch set yourself when I figure out how do it and I will have the hardware supporting MST. I have postponed my purchase of Surface Pro 2 due to personal circumstances, so anyone who has MST hardware and Surface Pro 2 is very welcome to go ahead and install a patch set and try it out and/or help Michael debug it, to assure that when the patch does arrive, it will work well on SP2, as right now MST support seems to be tested on Thinkpad T440s and 4K monitors.

You should be able to use two monitors, one way or the other, unless Microsoft relies on some secret sauce (software, firmware or hardware) that won't work with Ubuntu.

Surface Pro 2 ships with either i5-4200U or i5-4300U CPU, both Haswell chips with HD Graphics 4400 GPU. According to Intel, these chips have 4th generation graphics (HD Graphics 4200 and up is 4th, 4000 and 2500 is 3rd) and thus support DisplayPort 1.2.

Apart from graphics adapter support, you will need compatible monitors. These monitors should be DisplayPort 1.2 compatible and feature two DisplayPorts (for input and output). According to this page from DisplayPort.org (click 'DP Displays Multi-Stream' then 'Search') there are currently seven such models:

Or, you could use DisplayPort 1.2 MST hub like this one: not quite daisy-chain, but a solution to connect up to 3 DisplayPort monitors to a single DP 1.2 MST output. The monitors can be regular old-school DP 1.0, according to this answer.

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Nickolai Leschov
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Daisy chain support is in stable Linux kernel now. Please see my answer https://askubuntu.com/a/552094/349788 If Surface Pro has Intel graphics abroad then chain is likely to work at new Linux kernel and latest video drivers.

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kza
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