Dual card setup
 

Greetings

Running on Debian testing.

I have two nvidia 570 cards with four displays connected.

Any ideas how to get things to work using all the resources?

(xrandr active on only one card and two displays)

Any way to specify that DVI-I-3 and DVI-I-4 are active?

Does one have to set up xorg.conf with a massive virtual desktop (7680 x 7680) to get things to work?

Any ideas would be appreciated!!

D

Re: Dual card setup
 

Hi!

Please check "Chapter 14. Configuring GLX in Xinerama"
in the file "/usr/share/doc/NVIDIA_GLX-1.0/README.txt"
on how to setup a multi-monitor system with multiple GPUs.
There's also plenty of information on "Xinerama" in this
forum or on the web.
However, please note that Xinerama has a couple of limitations
which may or may not be a problem for you. For details on
this topic, please refer to
http://www.nvnews.net/vbulletin/showthread.php?t=133740

regards

Bernhard

Re: Dual card setup
 

Thanks you very much for your response Bernhard!

I actually have a copy of the forum conversation you pointed at on the other computer. It was this conversation that gave me the idea of creating a large (7680 x 7680) desktop. I think its xrandr that says that I could do 8192 x 8192. The system actually sees DVI-I-3 and DVI-I-4 which makes things even more frustrating.

What I am finding difficult to understand is that your conversation was from mid 2009 (almost a full 3 years ago). Randr has been promised upgrades for at least that length of time and the Nvidia GLX readme text is from 2006. Somehow I didn't think that what I wanted to do would be so 'out there'.

I just wanted to be able to have a large spreadsheet open (perhaps two screens) then have another spreadsheet open on a third screen and still have a screen to access information that would feed in either of the other two directions. This doesn't totally even work the way I want on the Win7 side.

Having the screen real estate available tells me that I should have had this long ago but I dispair of getting something that isn't a cludge working on any linux variant.

Thank you for your assistance!!!!

Re: Dual card setup
 

Just to throw in my 2 cents:

don't expect this setup being easy,
don't expect this setup being free.

Why? This is a very specialized setup. People needing something like that are either:
Wall St. professionals with lots of money,
construction / engineering firms with money too,
people wanting it and having the money to buy the equipment and time to tinker with it.

I, for one, cannot test your setup. Mine runs (2 monitors on one card). I would have to get another expensive card (ok, I have one), throw it into a computer, reconfigure the comp, get another monitor (only have one and could test a 3 monitor config; would need a 4th to do 4-way testing).

So, conclusion of the above:
you either have the money to pay someone doing it for you,
you have the knowledge to do it yourself,
you have the time to tinker with your equipment and gain the knowledge to do this in the future (and maybe make some money out of this knowledge).
These are the facts and you have to live with them :)

...before someone starts to flame me being rude: sarcasm intended.

Re: Dual card setup
 

I do hope that I am allowed to respond to your comments.

I see myself as a businessman NOT as a money bags.
I see myself as wanting to use technology not needing to create it.

I am finding that Linux is becoming its own most perfect enemy! Your response above is more than somewhat similar to the RTFM kind of responses that are all to familiar when I wish to USE technology. There seems to be a thinking out there that this technology is unusual. Well - - there were individuals trying it in 2003 (IIRC!!) using dual cards to achieve more than one monitor. Even better - - there are notes that indicate - - - wait for it - - - real soon now for multi-card support dating from 2009. Now if I were using this as a gaming rig there would be no real issues - - I would be running Win7 and I would not be worried about most of these issues. So your comments that I need either deep pockets or a boundless amount of time indicate to me that you think that using a computer seriously as a tool should require those things. As my motherboard is capable of holding a third card you might understand that this level of problems with two cards is more than somewhat astounding to me. I don't mind working on things but having spent well over a hundred hours trying to get this particular aspect working tells me that the idea you present of it taking 'time to tinker with it' shows that you don't value your time much.

If I could actually find someone who would actually be able to devise something for me I would likely be more than somewhat willing to pay for it. To give someone a blank check to have them create a solution - - well - - then I get to own it and its rights. Right now there really aren't even any tools out there to assist in this process. I am not a programmer but I have been trying to read and understand the code that is present in the Xorg files. What I am seeing is that most of the stuff in there is old. There is very little that is less than 3 years old. Xrandr updates have been pushed back at least twice - - why is not clear. Perhaps it is time for a solution that is not necessarily elegant but that is functional!!! Best is often the enemy of good enough.

By the way the idea of multiple monitors for CAD work is something I was reading about in the early 1990's - - so I don't really see what I'm trying to do as 'new'!

So - - do you have any suggestions as to where I could look for ideas to actually implement my ideas?

Re: Dual card setup
 

Hi. I'm not sure how much help I can be in this, but I'll give a try. I run two different cards with one monitor each, and setting them up was interesting. I had to do quite a bit of reading and googling to get things the way I wanted, so I should at least be able to point out some pertinent docs.
Have you got the nvidia driver running exclusively (ie. making sure that the nouveau driver doesn't load at all)? I found this to be extremely important as a first step to getting things started on the right foot. I am running debian unstable so at least we are running similar releases.
As a starter, I will list a few docs I found helpful:

https://wiki.archlinux.org/index.php/NVIDIA
http://www.gentoo.org/doc/en/nvidia-guide.xml
http://wiki.debian.org/NvidiaGraphic...n-free_drivers
http://wiki.debian.org/NvidiaGraphicsDriversNvidiaWay
http://www.suse.de/~sndirsch/nvidia-...ler-HOWTO.html
http://www.fedorafaq.org/#nvidia

The Arch, Gentoo, and Debian documents I used because all three have information important to any linux/nvidia install. The Suse and Fedora links I included in case you decide to try one of those distros.
There are other guides and howto's out there, and for other distro's, but the first three were the ones that got me on the right track. I'm not telling you to RTFM. Just if you want to get started, that I think these are good starting points for these distros. In any case, I'd be glad to help.

Also, let me add the official doc from Nvidia:
http://us.download.nvidia.com/XFree8...DME/index.html

If all this is old hat to you, I apologize for my long wind. If this is the case, and you have tried making adjustments via the gui - nvidia-setting control panel, direct edit of xorg.conf, and/or use of xrandr, perhaps another option is to consider different window managers.

Regards,
John

Re: Dual card setup
 

Thank you for your list of links.

I am at present a Debian user (like the long time between upgrades). I am running both Debian stable and testing on this rig and its the Debian testing that has proved to be quite troublesome!

I had mostly looked for Debian specific information so I do need to go through what you have indicated carefully. I was reading the Nvidia 295.20 readme this morning and with all the options its still not clear how to set up a dual card system. Multi monitor seems quite easy - its the multi card option that is proving to be so difficult. As I have been thinking of using a third card for more graphics (or CUDA) acceleration this is somewhat important to me.

I will indicate my success after I have had time to carefully read through your materials!

Thank you for your assistance!!

Re: Dual card setup
 

I just was thinking, that you should make sure that your two cards are not setup for SLI. SLI will supposedly not work for what you are trying to accomplish.
Also, once you have made sure that nvidia and not nouveau is the only video driver:
in /etc/modprobe.d/fbdev-blacklist, add:
and then
to make sure modules aren't loaded from the initramfs.
Then you can reboot into single user mode to have a fresh environment (this will be as root); run:
Review the resulting xorg.conf and also check the /var/log/Xorg.0.log for errors.
You can test the new xorg.conf with:
Don't forget, if there is a problem with X hanging, then cntrl-alt-F1 with take you back to a terminal,
then you can manually kill the server if you have to:
Sorry if you knew all this, but I'd rather you didn't have to get stuck with a hung X server and think you had to hit the power switch or something else with possibly catastrophic consquences (it ain't fun trashing your filesystem).

The cleaner the config to start with, the easier it should be troubleshoot/trackdown
issues later. By the way, be sure to save /etc/X11/xorg.conf and any other files you will be changing/replacing before messing with them, so at least you can go back to a known working configuration.

Cheers,
John

Re: Dual card setup
 

good lucky to you!
http://www.rqsulfates.com

Re: Dual card setup
 

So -- having had some time to peruse the documents listed I haven't been able to find any reference to multiple cards. There is information re: multiple monitors but its the dual card thing that is giving me almost all the issues.

So we continue looking for some reference to multiple cards - - thanks for the suggestions!!!

Re: Dual card setup
 

Good luck.

Re: Dual card setup
 

I did some searching using google trying to find exactly what a SLI implementation is. It is clear that it is two or more GPUs working together. What I cannot find is exactly what causes this!

Is the connector that links the two GPU cards across the top the only thing that needs to be removed to remove SLI?

If one had three cards does one then see 2 GPU cards or not?

This is somewhat confusing - - do you have any ideas John?