[Sussex] 2 monitors, one machine

[Chris Jones]

Hi

(cc'd back to the list, so it ends up in the archives, for what it's worth)

On 11:42:44 pm 06/10/2005 Anthony Rangecroft <ar at f2s.com> wrote:
> Can you say a bit more about how you've implemented it, what works
> well about it and what the limitations are (and why you don't mind
> them)?

I certainly can, although I should point out that this is entirely nVidia
specific.

How I did it is currently documented here in the quick and dirty guide here:

https://wiki.ubuntu.com/XineramaMultipleMonitors

That page is due to be rewritten though, so that information will disappear
at some point. You can reconstruct it all from reading nVidia's docs, it
may just take a bit longer ;)

What works well is pretty much everything. As I understand it, a
traditional Xinerama multiple head setup has great difficulty doing things
like Xv/3D acceleration across the different video cards (it was the case
when I last tried it and it is a very hard problem). Twinview (nVidia's
dualhead system), however, is hiding all of the details from X. My X server
honestly thinks I have a 3200x1200 monitor. It's only because of the fake
Xinerama extension Twinview inserts that applications can tell where the
monitor boundaries are (sadly not everything is Xinerama aware yet, but
anything gnome/kde stands a reasonable chance).

> The interface for controlling the displays - where dialogues appear,
> where applications launch etc. - was miserably confused and erratic

metacity isn't great at this, but the problem is being worked on and other
window managers may well be betters.

> to the point of some operations not being repeatable.  The worst was
> that there was no way to simply exchange the 2 displays between the 2
> monitors.

Twinview and Xinerama both make this quite easy, you simply tell them where
the monitors are in relation to each other. At work I have my second head
on the left of the main one, at home on the right. With the right extra
twinview option at work it knows to match up the edges of the monitors
properly. The second head at work is even a smaller resolution, so I have
some dead space in the desktop, but xinerama aware things will ignore that
space.

Xinerama will be fine for simple workstation tasks, but you'll really want
something like Twinview or a high end Matrox card maybe, to get things like
multimedia or gaming or visualisaion type tasks working properly. This
places severe restrictions on choices of card and means using non-free
software unfortunately.

Thankfully nVidia cards can be bought quite cheaply and even the basic ones
have the grunt to do a decent dualhead desktop, if you don't care much for
gaming. Also Ubuntu has great support, yay, all hail ;)

Cheers,
---
Chris Jones
  cmsj at tenshu.net
  www.tenshu.net