[ltp] External video on T61

John Jason Jordan linux-thinkpad@linux-thinkpad.org
Fri, 23 May 2008 12:22:29 -0700


On Tue, 20 May 2008 10:40:27 +0300
Micha <michf@post.tau.ac.il> dijo:

> On Mon, 19 May 2008 16:55:27 -0700
> John Jason Jordan <johnxj@comcast.net> wrote:
> 
> > On Mon, 19 May 2008 17:21:08 -0500
> > Pablo Vera <pvera@vercan.com> dijo:
> > 
> > > As suggested on the mail by Christoph, you should use nvidia-settings.
> > > 
> > > Open a console and type: sudo nvidia-settings, provide your password and 
> > > select "X Server Display Configuration" on the left panel.  From there 
> > > you will see that the driver detected both the internal LCD panel and 
> > > the external projector, but the projector is disabled.  Click on the 
> > > projector, enable it and set it up as you see fit.  Finally press: "Save 
> > > to X Configuration File" and you are done.  Log off and re-login and it 
> > > should work.

> > I managed to get it to work using nvidia-settings, except the projector
> > is displaying on the screen only about 1/4 of my screen. My screen is
> > 1680 x 1050. In "X Server Display Configuration" the projecter options
> > are Auto, 320 x 240 and 640 x 480. I need to be able to set it higher
> > in order to capture all the screen of my laptop, but the choice is not
> > there.

> The only option that worked for me at the time was to set the external screen
> to 640x480 and disable the internal screen using nvidia settings. Don't save to
> xorg.conf or you will have trouble later on.
> 
> This will set your desktop to 640x480 and will work with the projector. Setting
> the resolution back can be a pain so if  you didn't save the settings you can
> just restart x.

Someone locally suggested holding down Fn+F7 but before the kernel
boots. I tried it just now, and it worked. Sort of, that is.

First, let me say that normally I use a bluetooth mouse, but I swapped
for a USB cordless mouse and got the same results as below.

Let me also say that I did all this with with a roll-around console in
the classroom. The console contains a PC (Windows XP), a VCR, a DVD
player, and all are connected to network, and via video cables to a
Hitachi projector in the ceiling. The console also has a control panel
with buttons to turn on the projector, select "laptop" instead of "PC,"
and input plugs for video and audio from the laptop. On top of the
console is an LCD display that normally functions as the monitor for
the Windows XP PC. At the time I did this the Windows XP PC was not
running.

After connecting a video cable between the T6a and the input plug on
the console I booted Hardy, but held down Fn+F7 until the Grub boot
menu came up. Hardy booted fine, except that the display screen on my
T61 was not my normal Gnome desktop. It was Gnome, but as it looks like
right after a fresh install of Hardy. Almost all of my personal
settings were not there. However, the screen wallpaper was as I had set
it. I have no idea where this desktop came from.

At the same time, the LCD monitor on top of the console displayed my
normal desktop, although in 640 x 480 instead of the 1680 x 1050 on the
T61 display. And while the T61's display showed the strange "default"
Gnome desktop, it *was* at 1680 x 1050. How bizarro is that?

Throughout, whatever was on the LCD monitor on the cart was also
displayed on the wall screen by the projector. 

At first the mouse worked on both the T61's display and on the LCD.
After about 60 seconds it stopped working on the LCD. It continued to
work on the T61's display. 

The keyboard also stopped working on the LCD display, except once in a
while I could get a reaction from it. Meantime it continued to work
find on the T61's display.

I opened nvidia-settings on the T61's display (because it was
impossible to do anything on the LCD display without a mouse or
keyboard), and I poked at everything, but nothing I did got the mouse
or keyboard working on the LCD display.

Eventually I gave up and decided to ask here for further advice. What a
strange experience!