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I'm using a single nvidia Quadro FX 3700 card on my system.

This thread:

How to set up a multiseat system?

suggests that changes should be made to the lightdm.conf and xorg.conf files. When I made the suggested changes to xorg.conf and the following

displays=display0 display1





changes to lightdm.conf, from what I remember, ubuntu failed to detect my second monitor. Other information I've found gives directions for older versions of ubuntu which use different display managers (gdm as opposed to lightdm), which doesn't help. I also tried using

but it didn't detect my second monitor so I couldn't follow the directions given. In the first thread I linked to somebody claimed "In terms with running multiple X sessions from one video card this is currently unsupported." which suggests that it might not be possible with my current setup.

I don't really know what I'm doing, I'm just trying to follow any resources that are available. So how do I do it? Is it even possible with 12.04 and only one video card?

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AMD radeon does support multiple desktops and multiple screens, and AMD's (4-core) APU (CPU and GPU in one) does support 3d gaming with 4 users, 4 screens, in HD.

Nvidia is not the best card to have when you're using linux.

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I've less trouble wing nVidia than ATI. ATI often will fail to boot. – hexafraction Sep 24 '12 at 12:35

I've tried a lot to set up a multiseat system in one video card, although I just find instructions for two video cards, as you can see in the MultiseatX section of Ubuntu help page.

Running multiple X sessions in one videocard is impossible, but you can do the impossible (>.<) with Xephyr, atlhough you'll be working with stones to accomplish that. I would recomend you to buy another graphic card to setup a multiseat, but if you can make juice from rocks, codding around... go on, you can find this useful:

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I just wanted to point to a site that has suggestions that seem to have fixed my system instability issues:

I followed the above instructions but had system crashes until I implemented the options described on the above blog.

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