Arch Linux

2scomplement

Member

Registered: 2010-05-14

Posts: 3

IBM T61 No VGA output

Hi everyone,

I can't seem to get any display on an external VGA panel. The panel is detected -- xrandr shows it as connected, and correctly auto-detects the modes -- but no image is displayed:

$ xrandr
Screen 0: minimum 320 x 200, current 1024 x 768, maximum 4096 x 4096
LVDS1 connected 1024x768+0+0 (normal left inverted right x axis y axis) 286mm x 214mm
   1024x768       60.0*+   50.0  
   800x600        60.3     56.2  
   640x480        60.0     59.9  
VGA1 connected 1024x768+0+0 (normal left inverted right x axis y axis) 477mm x 268mm
   1920x1080      60.0 +
   1680x1050      60.0  
   1280x1024      75.0     60.0  
   1152x864       75.0  
   1024x768       75.1*    60.0  
   800x600        75.0     60.3  
   640x480        75.0     60.0  
   720x400        70.1  
DVI1 disconnected (normal left inverted right x axis y axis)

The monitor is also aware that the laptop is connected -- when the cable is unplugged it displays a signal error message, when the cable is plugged into the laptop however it goes into power saving.

The display works fine on another (Windows!) laptop, so the issue is not a hardware fault with the monitor. This laptop did work a year ago with an external monitor, although my configuration has changed since, so this is a possible X regression.

Graphics are Intel GM950. I am using kernel mode setting for the Intel graphics.

Right now I'm stumped as to what to do: I know the hardware should support it. I'm using this laptop as my main desktop system so external monitor support is a crucial feature, but I'd prefer to avoid having to either change operating system or buy another laptop. If you could give any advice as to how to go about debugging this I'd appreciate it!

lagagnon

Member

From: an Island in the Pacific...

Registered: 2009-12-10

Posts: 1,087

Website

Re: IBM T61 No VGA output

Does it work if you reboot with the VGA panel connected?

---

Philosophy is looking for a black cat in a dark room. Metaphysics is looking for a black cat in a dark room that isn't there. Religion is looking for a black cat in a dark room that isn't there and shouting "I found it!". Science is looking for a black cat in a dark room with a flashlight.

2scomplement

Member

Registered: 2010-05-14

Posts: 3

Re: IBM T61 No VGA output

Does it work if you reboot with the VGA panel connected?

Good suggestion. Unfortunately it does not. Interestingly when I do that I see nothing on the LVDS screen until ArchLinux boots (no BIOS screens), suggesting that it is sending something to the VGA -- however I see nothing on the VGA panel either.

natestar13

Member

From: Tampa, FL

Registered: 2012-01-16

Posts: 55

Re: IBM T61 No VGA output

You stated that the VGA was working with this laptop a year ago.  Does it work if you try booting to another Linux OS on the same laptop?  It could be the VGA port went bad.  If you only have one OS on this laptop, try booting into a LiveUSB or LiveCD

---

Machine:  Lenovo ThinkCenter M92 (M3209) - Inte i7-3770 CPU