Hi. My problem is that I can't install Ubuntu 12.X and 11.X versions on a DELL precision 670 Processor Intel dual xeon and a video card for double screen.
I tried using a Live DVD and a USB device for both cases and the screen (at the beginning and after of options of TRY and INSTALL) shows the following text when I click on TRY Ubuntu:

[xxxxxxxxx] [DRM] nouveau 0000:05:00.0 GPU lockup - switching to software fbcon
[xxxxxxxxx] [DRM] nouveau 0000:05:00.0: Failed to idle channel 1.
[xxxxxxxxx] [DRM] nouveau 0000:05:00.0: Failed to idle channel 2.
[xxxxxxxxx] [DRM] nouveau 0000:05:00.0: Failed to idle channel 3.
[xxxxxxxxx] [DRM] nouveau 0000:05:00.0: Failed to idle channel 1.

I don't know if Ubuntu would work well just installing...

So, I tried with Ubuntu 10.10 and the Live DVD worked fine from the DVD_ROM What kind of problem could be? Something related with the video card?

I tested a DELL Precision 380 with the Live DVD Ubuntu 12.10 and it works fine.

Regards.