I am just about to order a second 17" TFT to match my existing one, I noticed where I was doing some DVD Authoring last week that I need more screen estate.
I would like to stay with Nvidia cards if at all possible, partly because I need good hardware 3D on at least one screen and partly because I know where I can grab a really good dualhead Nvidia card really cheap.
Not having done this before I would like to know how it all works before I commit to the extra screen. How for example do the virtual desktops interact with dual head, Do I used the desktop pager in the normal way and choose which display has which desktop ?
How does the framebuffer work, does this only work on the first screen ?
Has anyone used VMware on a dual head setup, what happens if you set a VM to fullscreen ? Does it go fullscreen on one of the monitors and do you have any choice about which screen that is ?
When I was googling about I saw loads of references to xinerama and twinview and other sites that just said to add the second display to the xconfig file. What method should I use to get the behaviour(s) above ?
On Sun, Nov 06, 2005 at 05:12:52PM +0000, Wayne Stallwood wrote:
I would like to stay with Nvidia cards if at all possible, partly because I need good hardware 3D on at least one screen and partly because I know where I can grab a really good dualhead Nvidia card really cheap.
Does your existing Nvidia card have dual outputs? and are you using the non-free driver? If yes, then use Twinview as it works outside of X and basically presents a single large screen (AIUI) which just acts as a normal single display (albeit over 2 screens). The other method using Xinerama involves configuring 2 seperate cards and then glueing the 2 displays together (I think). I've only ever used the former method, which worked very well and seamlessly (and this was 3 years ago now).
Thanks Adam
On Sun, 2005-11-06 at 18:35 +0000, Adam Bower wrote:
Does your existing Nvidia card have dual outputs?
No it is a single output GF4 of some kind.
and are you using the non-free driver?
Yep
If yes, then use Twinview as it works outside of X and basically presents a single large screen (AIUI) which just acts as a normal single display (albeit over 2 screens). The other method using Xinerama involves configuring 2 seperate cards and then glueing the 2 displays together (I think). I've only ever used the former method, which worked very well and seamlessly (and this was 3 years ago now).
Ahhh cool, that sounds more simple than the scenario I was imagining with a virtual desktop per display. Doesn't that sort of break things that want to run in fullscreen mode ? How does it behave if something (for example a game or dvd playback ) tries to go fullscreen (as in no window border) Does it just go fullscreen on the first display (desired operation) or does it try and span both screens.
On Sun, Nov 06, 2005 at 06:54:29PM +0000, Wayne Stallwood wrote:
Ahhh cool, that sounds more simple than the scenario I was imagining with a virtual desktop per display. Doesn't that sort of break things that want to run in fullscreen mode ? How does it behave if something (for example a game or dvd playback ) tries to go fullscreen (as in no window border) Does it just go fullscreen on the first display (desired operation) or does it try and span both screens.
It will go fullscreen on both displays as effectively they are 1 big display. I don't know if Xinerama fixes this or not... (i'd take a guess that the window manager would need to be Xineram aware) but most people I knew would resize the applications manually.
Thanks Adam
On Sunday 06 November 2005 19:02, Adam Bower wrote:
It will go fullscreen on both displays as effectively they are 1 big display. I don't know if Xinerama fixes this or not... (i'd take a guess that the window manager would need to be Xineram aware) but most people I knew would resize the applications manually.
I use an assortment of ATI cards to run a triple head display - KDE fills all three screens quite nicely. Opening an app and "full sizing" it, and it occupies one of the three monitors. To expand it to cover all three requires a simple click'n'drag operation.. Doing this with a text konsole has exposed a couple of hickups with one or two text based programs (for some reason, one or two can not cope with screens wider than 256 characters).
Regards, Paul.
** Adam Bower adam@thebowery.co.uk [2005-11-06 19:09]:
On Sun, Nov 06, 2005 at 06:54:29PM +0000, Wayne Stallwood wrote:
Ahhh cool, that sounds more simple than the scenario I was imagining with a virtual desktop per display. Doesn't that sort of break things that want to run in fullscreen mode ? How does it behave if something (for example a game or dvd playback ) tries to go fullscreen (as in no window border) Does it just go fullscreen on the first display (desired operation) or does it try and span both screens.
It will go fullscreen on both displays as effectively they are 1 big display. I don't know if Xinerama fixes this or not... (i'd take a guess that the window manager would need to be Xineram aware) but most people I knew would resize the applications manually.
** end quote [Adam Bower]
I've just sorted out dual head with a nVidia MX440 and an old Matrox Millennium II. Under that setup with Xinerama most applications maximised and opened to a single screen. I seem to remember one opening in the middle with half on each screen, but non maximised across screens. This of course is two cards and not a single one. I've just replaced the MX440 with a FX5200 which worked dual head quite easily under Windows once I'd got my hands on a DVI-VGA adaptor. I've not yet sorted out the nVidia drivers to get it dual headed with Twinview though.
The idea that it treats the whole thing indiscriminately as a single screen is a little disappointing, but I'll know better when I've tried! I'm considering switching to X.org (currently XFree86 still) before I start configuring, but then again I've done it with my current setup so getting dual head sorted first might make sense (particularly as Debian testing hasn't got X.org in yet (oops, ignore that, somebody snuck it in while I wasn't paying attention!).
I just need some play time :)
On Mon, Nov 07, 2005 at 12:14:34AM +0000, Paul Tansom wrote:
The idea that it treats the whole thing indiscriminately as a single screen is a little disappointing, but I'll know better when I've tried!
Well, I'm not entirely sure to be honest how twinview (now) deals with 2 screens. I'm going on what I was doing with it 3 years ago, and at the time we wanted it to be dealt with as 1 giant (and very wide) screen at the time because we were doing movie related work that needed things to be widescreen.
Adam
On Sun, 2005-11-06 at 17:12 +0000, Wayne Stallwood wrote:
I am just about to order a second 17" TFT to match my existing one, I noticed where I was doing some DVD Authoring last week that I need more screen estate.
I would like to stay with Nvidia cards if at all possible, partly because I need good hardware 3D on at least one screen and partly because I know where I can grab a really good dualhead Nvidia card really cheap.
Replying to the list this time.... D'OH !
I can't help much as I use ATI cards, but dual headed supports comes in various forms.
With ATI drivers I choose to have "one big frame buffer" that covers both monitors and runs with one window manager. Hardware acceleration (I use openGL) works on both monitors (as there is only one frame buffer).
Alternatives provide a frame buffer for each monitor, which can be used independently (2x window managers) or together with xinerama, but I would guess anything in the driver is going to be more efficient than xinerama at putting them together. BUT xinerama may be able to put more than just two together.
I'll be trying to put 2x ATI X800s in a box soon (quad headed!)
Peter
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Wayne Stallwood