Ubuntu
xserver-xorg-video-mga package

Black screen with dual-head on Matrox G45FMDVP32DB /32MB /DVI /VGA

Bug #1183420 reported by Jaromír Cápík on 2013-05-23

6

This bug affects 1 person

Affects		Status	Importance	Assigned to	Milestone
	xserver-xorg-video-mga (Ubuntu)	New	Undecided	Unassigned

Bug Description

Hello.

After resolving the following dual-head related crashes ...
https://bugs.launchpad.net/ubuntu/+source/xserver-xorg-video-mga/+bug/1180986

... a new problem was encountered.

I get only a black screen when starting X with dual-head config.
However, when I switch to a working single screen config and then back to dual-head, it works like expected.
I have to repeat the procedure after each reboot in order to make it work.

I'm willing to collect any debug info you need.

Please, let me know.
Thank you.

Regards,
Jaromir Capik

Revision history for this message

Jaromír Cápík (tavvva) wrote on 2013-05-23:

#1

xorg configs & logs + diff Edit (41.7 KiB, application/x-tar)

Revision history for this message

Jaromír Cápík (tavvva) wrote on 2013-05-23:

#2

maybe some additional notes ....

The first try ( xorg.conf-1.txt / Xorg.0.log-1.txt ) leads to a black screen on both monitors ...
The second try ( xorg.conf-2.txt / Xorg.0.log-2.txt ) leads to the same content on both monitors ...
The third try ( xorg.conf-3.txt / Xorg.0.log-3.txt ) leads to a different content on both monitors (correctly working dual-head) ...

I included logs with stripped timestamps and diff between these stripped versions for a faster analysis ... but I see no major difference between the 1st and 3rd try.

Revision history for this message

Jaromír Cápík (tavvva) wrote on 2013-05-23:

#3

I just did some tests here ...

Even when the screen is black in the first case, the signal seems to be present on the monitor plugged in the D-SUB connector (it says it's receiving 1024x768x75Hz with 60kHz hsync). The second monitor plugged in the DVI connector [via DVI to DSUB converter] doesn't even have any signal.
The black screen on the monitor that receives signal was caused by the MDM login manager .... it's apparently a correct behavior. I tried a blind login and got a desktop wallpaper on that monitor. So .... I must say the VGA output works like expected. Just the DVI connector needs to be waked up with the single screen config .... Maybe just the analog part of the DVI connector isn't initialized well. I'm going to borrow a digital monitor and test that again.

Revision history for this message

Tormod Volden (tormodvolden) wrote on 2013-05-23:

#4

Please attach files one by one, plain text.

Revision history for this message

Jaromír Cápík (tavvva) wrote on 2013-05-23:

#5

xorg.conf-1.txt Edit (6.7 KiB, text/plain)

Revision history for this message

Jaromír Cápík (tavvva) wrote on 2013-05-23:

#6

Xorg.0.log-1.txt Edit (52.8 KiB, text/plain)

Revision history for this message

Jaromír Cápík (tavvva) wrote on 2013-05-23:

#7

xorg.conf-2.txt Edit (4.4 KiB, text/plain)

Revision history for this message

Jaromír Cápík (tavvva) wrote on 2013-05-23:

#8

Xorg.0.log-2.txt Edit (35.0 KiB, text/plain)

Revision history for this message

Jaromír Cápík (tavvva) wrote on 2013-05-23:

#9

xorg.conf-3.txt Edit (6.7 KiB, text/plain)

Revision history for this message

Jaromír Cápík (tavvva) wrote on 2013-05-23:

#10

Xorg.0.log-3.txt Edit (52.8 KiB, text/plain)

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