A question for the family gearheads...

[spiel2001]

There seems to be a family of pretty sharp gearheads here in nUI land... Any Linux types out there?

I'm having an issue getting X to span desktops for me. Anyone have an idea if this is a video card/driver thing or an X config thing?

Under Red Hat Enterprise Linux Server 5, if I select display from system administration and enable dual head I can configure the displays no problem and run dual desktops on them. But the moment I enable desktop spanning and log out/back in, X won't start and I have to revert to the default config before I can get X started again.

Anyone know anything about this?

[Xrystal]

Now that is one area I tried to avoid. I'd ask my brother but at 4am I think he will kill me

Hopefully someone out there has a smidgeon of knowledge of Linux to help you out there

[Yhor]

I saw an answer to this somewhere, I'll see if I can dig it up. What card are you using btw, just in case?


Edit: Found a couple links to start off, both seem appropriate. I'll keep looking for the one I saw that was a pretty awesome guide for both nvidia and ati, and also covered some various desktops.

In the mean time..
Related to Kubuntu 5.04 and using ATI (but generally applicable)
http://www.granneman.com/techinfo/li...lheadhowto.htm

Some generally helpful tips. (Ubuntu, Fedora, etc..)
http://www.linuxquestions.org/questi...nitors-689888/

[spiel2001]

Yeah... this is a trashy onboard Intel video chipset... one VGA output and one DVI output. I can't recall the exact chipset number, but I'll look it up tomorrow when I have physical access to the machine again.

And thanks Yhor.

[Seer]

Last time I had a similar problem (long ago), tho not on Red Hat (or a "server" install) a reinstall was the only way to get it working properly.

And the weird part was, the first install was less then a week old, done with the same disc, using the same install options (iirc). After the second install it worked like a charm.

[Yhor]

Originally Posted by spiel2001 Yeah... this is a trashy onboard Intel video chipset... one VGA output and one DVI output. I can't recall the exact chipset number, but I'll look it up tomorrow when I have physical access to the machine again. And thanks Yhor.

As far as I know, I've never heard of on board video being able to do this, at least not without a program to implement it. Hopefully I'm wrong or you can find something to get you going. I'm still looking for that guide, as I find time.

Good luck.


*Seer, were you using on board video, if you can remember?

[Mycroftxxx1]

Our work desktops, HP DC 5000, use on board videos IIRC and can handle dual video using a special dual-head cable.

[Seer]

Originally Posted by Yhor *Seer, were you using on board video, if you can remember?

No, was some kind of nVidia AGP card IIRC,


I know Lenovo has some kind of weird "adapter" in a PCI slot that looks like a DVI connector (a bit different then the normal DVI that holds both digital and analog signals) that only seems to work with Vista. Offcourse I can't find any machine here at the moment that has this adapter still inside (most monitors are VGA here, and we need to use XP) and Lenovo uses mostly intel IGPs but also nVidia and ATI chips..

[Telepavarion]

Yeah but most of the Lenovo graphic cards are made for CAD and not for 3D output.

I had some problems on my ThinkPad with Ubuntu 8.04 Hardy. It takes really a long time to get it really good work with 2 displays. But I dont can say anymore what's exactly I done. I switching back to Vista, because of a 3D CAD Programm from Siemens which only run under Windows.

[spiel2001]

Have you tried Wine?

http://www.winehq.org/

[Telepavarion]

Of course, but SolidEgde goes to deeply into Windows as Wine can handle it easily. The biggest Problem are my IntelVideo Chip, because it isn't translated correctly and I see a black screen.

Yeah I really miss Ubuntu sometimes. It has some very nice functionallity and runs very fast, but alltimes to use a dualboot system isnt nice and so have have to switch back. I have read it runs on Linux, but only with full compatible VideoCards. My ICH-9xx isn't it.

[KruesephiikZ]

I seem to remember this being a driver issue entirely. Spanning desktops hasn't worked correctly with X.Org forever, cept with nVidia cards. Span the desktop, change the resolution, change it back then see if it'll start up. For whatever reason that worked for me in the past when I had an ATI card. May be completely unrelated to your rig, but it might be worth a shot.

[spiel2001]

Yup... and the winner is... nVidia. We went out and got three nVidea cards and put one in each server, installed the drivers, booted, set the desktop to spanning and done.

We're going to experiment a bit more, but it looks like it is a driver/X.org thing.

My sincere thanks to everyone for their input.

[Yhor]

Glad ya got it working, sorry ya had to spend money .

[spiel2001]

Okay --

So, tonight we used the xorg.conf we built with the nVidea card that works, and replaced the nVidea card/driver names with the Intel/Vesa card/driver names and booted.

The good news is that unlike before, X did not crash and the servers woule boot into X11. However, the spanning failed and we still had cloned desktops.

So... the moral of the story is that the Intel chipset and drivers clearly just won't support spanning in X11. The nVidea solves it and we were able to do it with $44 cards, which is far less than the time it would take the engineers to resolve it any other way.