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Sharky0815
08-08-2005, 12:26 PM
I tried posting this over at the Ubuntu Forums but sadly got no reply. I know that this is not a linux forum but I've got the feeling someone here could help me.

I'm planning to set up multi-monitoring for a Maya Workstation, using an nvidia card. I am bit confused how to do it. As far as I understand these are (some of?) the options:


Running two X servers off one card
Running two X servers off two cards
Using nvidias inbuilt driver options

How is nvidias dualhead implementation different from running two X servers? How do virtual desktops work with two or more monitors? Do resolutions have to be matched? What is Xinerama? What about hardware acceleration in both windows? What would be the pro's and con's of running two X servers? How much does using a second graphics adapter help performance and are there any negative side-effects?

I know this is a lot of questions, I'm not expecting to get them all answered, just to show my general confusion with this topic.

Thank you for your time!

Kai01W
08-08-2005, 12:33 PM
I tried posting this over at the Ubuntu Forums but sadly got no reply. I know that this is not a linux forum but I've got the feeling someone here could help me.

I'm planning to set up multi-monitoring for a Maya Workstation, using an nvidia card. I am bit confused how to do it. As far as I understand these are (some of?) the options:


Running two X servers off one card
Running two X servers off two cards
Using nvidias inbuilt driver options

How is nvidias dualhead implementation different from running two X servers? How do virtual desktops work with two or more monitors? Do resolutions have to be matched? What is Xinerama? What about hardware acceleration in both windows? What would be the pro's and con's of running two X servers? How much does using a second graphics adapter help performance and are there any negative side-effects?

I know this is a lot of questions, I'm not expecting to get them all answered, just to show my general confusion with this topic.

Thank you for your time!


Hi,

I'm using a dual monitor SetUp on SuSE with the built in NVidia Driver Option ("TwinView") and I'd really recommend to do it like that since I had no problems with this setUp and I don't know about Maya and two X servers...
Plus Its rather easy to do (should be the same with Ubuntu)

-k

Sharky0815
08-08-2005, 12:48 PM
Thank you for your answer. I think you are right, using standard twinview is probably the best option. One more thing, how is opengl performance on the second monitor? No problems I assume? And how are the virual desktops handled?

greydef
08-09-2005, 10:20 AM
Thank you for your answer. I think you are right, using standard twinview is probably the best option. One more thing, how is opengl performance on the second monitor? No problems I assume? And how are the virual desktops handled?

In my experience Linux (Mandriva & Fedora) treats the NVidia dual displays as one screen as per your config file. When you use virtual desktops each desktop contains two screens so when you switch between desktops you switch between sets of two.

I haven't noticed any differences in performance between either monitor, but I've never really scrutinized their performances.

amirjahanlou
08-09-2005, 01:33 PM
Have tried Nvidia twinView on both RH and Debian ( On a Geforce 4 TI ).


Performance is the same ( At least with this card, I know some ATI cards would have different performance with Dual and Single on windows OS ), I don't beleive the Oopn Gl would be different on 2 monitors in any case.
As for the resolution it doesn't necessarily need to be same on both.

About Xinerma i haven't heard of it even.

YOu can also check http://www.nvidia.com/object/linux_display_ia32_1.0-7667.html If you haven't yet.

Cheers

Sharky0815
08-09-2005, 01:46 PM
People, thanks for the replies. I knew CGTalk was the place to go :thumbsup:. I'm really looking forward to my workstation, linux sure has come a long way since I last tried it two years ago... Feels good to have choices...

UrbanFuturistic
08-09-2005, 05:26 PM
OK, in short:

Two X Servers means that while you'll have two screens you'll also have two desktop which can't directly interoperate with each other. This means that you'll need two taskbars with a menu button each and you can't just drag a window from one screen to another or even necessarily share the clipboard as you'll most likely be running two seperate KDE/Gnome/whatever sessions for each screen.

nVidia TwinView is most definitely the way forward.

Resolutions don't have to be matched but you do need to specify what resolutions ie: what resolution the second monitor is to have if the primary monitor is at 1024x768. This should all be covered in the release notes from the nVidia website.

Xinerama is not something you have to worry about as this is all handled by twinview if you use the nVidia drivers. Xinerama extensions handle all the stuff that would otherwise be a problem if it was just a standard desktop spread across two screens such as making sure full screen video defaults to only one screen and maximising does likewise. Not every software handles this gracefully (previous versions of mplayer, for example, spread across both screens, then defaulted to the wrong screen) but last I checked even the visually confusing Softimage|XSI managed to maximise properly despite its habit of starting up across both screens.

Now, I know that with Twinview hardware acceleration is avilable across both screens, however I couldn't say for dual cards (which I believe only work with seperate X servers, at least without SLI) as the last time I set up a computer with this config was a few years ago but it used to be the case that hardware acceleration was only available on the first screen. Again, it's probably best to refer to the release notes which you're going to have to do for all the configuration options anyway.

regards, Paul

Sharky0815
08-09-2005, 06:23 PM
"In short" ? That was exhaustive, thanks for typing all this up! I see that twinview is definitely the way. But it never hurts to know a little background, especially with linux... Will check out the driver release notes, of course!

lots
08-11-2005, 10:31 PM
At work I run Gentoo, with 3 craptacular ATI RAGE 3D II's and one Geforce 2 MX. So, as you can imagine, I have a 4 monitor setup. Since none of these cards were designed with Twinview in mind, I just use xinerama. This, as stated earlier, means I have 4 separate x sessions going on at the same time. None of the screens can directly interact. For example I cant move window X on monitor A to monitor B, which is not too much of an issue. The neat thing is each display has it's own set of virtual desktops i can switch between.

In either case, this works for what I do at work (code some maintain stuff, etc). But with anything linux, you have many options. Twin view would be the best way to do this. It fools the Xserver into thinking the screen dimentions are the size of your two monitors, and handles things very nicely. Much like it does in windows. You also get 3D accelleration on both screens. I've done the Twin view thing on my machine at home, and it works fairly well. And really its a cinch to set up. You just set a flag in your X config file and you're set (for both twinview and xinerama).

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