Dual monitor on laptop with ATI

[jethro]

Hello everybody,

 

I have a new laptop (Toshiba Satellite M40-277) with the ATI Raedon Express 200M graphics card. Under windows this cards support the usages of dual monitors. This means that I can hook up an external monitor to my laptop and show different content on it than on my laptop screen. I then actually have 2 different screens which is very nice when you are programming and writting documents.

 

The screen of my laptop is a 15.4" widescreen, which I got working on the right resolution (1280 x 800) after some trouble. I used the ATI drivers for this: https://support.ati.com/ics/support/KBAnswe...questionID=1176. Now I want to set it up so that I can use an external screen (which has a different resolution) exactly like how I can use it under Windows, because I think it's a big advantage.

 

I tried running fgrlxconfig and choosing the "Big desktop" there, but this didn't gave the external monitor different content. It actually gave it the samen content in the same resolution. I think that there have to be made some changes in xorg.conf, but I have no idea what to do there. I'm a relative new user of Linux.

 

I'm using Mandriva 2006.

 

Best regards,

Jethro

[jethro]

No one has ever had this problem before? If I want to use a beamer (the same output) I have the same problem, so I'm not even able to give a proper presentation with my laptop under Linux. There must be some kind of solution for this?

[coverup]

My solution is to have two copies of XF86Config (or xorg.conf), one is configured for the LCD and another is configured for the projector. I believe, many have the same problem but keep quit because MDK/Mandriva sucks in this particular area. You'll find reports on the web that people successfully got dual screen working using Debian and the stock radeon driver. I've never seen any report on getting it work with MDK/driva.

[jethro]

Alrigth, but you can't use both of these together at the same time. So when you use the projector the lcd of your laptop is not useable, of I'm a getting it wrong?

 

It's really a shame that Mandriva works as it does at this point. Besides this thing I really love the OS.

[coverup]

Alrigth, but you can't use both of these together at the same time. So when you use the projector the lcd of your laptop is not useable, of I'm a getting it wrong?

<{POST_SNAPBACK}>

Precisely.

[jethro]

Hmmmm.... that's pretty crappy. I mean, if Windows supports something (in this case a dual screen), Linux must definitly support it to.

[ianw1974]

You could get it working with 2 monitors, but it would take a bit of tweaking. For example, here is some of my xorg.conf:

 

Section "Monitor"
   Identifier "monitor1"
   VendorName "Generic"
   ModelName "Flat Panel 1024x768"
   HorizSync 31.5-55
   VertRefresh 40-70
   DisplaySize 260 195

   # TV fullscreen mode or DVD fullscreen output.
   # 768x576 @ 79 Hz, 50 kHz hsync
   ModeLine "768x576"     50.00  768  832  846 1000   576  590  595  630

   # 768x576 @ 100 Hz, 61.6 kHz hsync
   ModeLine "768x576"     63.07  768  800  960 1024   576  578  590  616
EndSection

Section "Screen"
   Identifier "screen1"
   Device "device1"
   Monitor "monitor1"
   DefaultColorDepth 24

   Subsection "Display"
       Depth 8
       Virtual 1024 768
   EndSubsection

   Subsection "Display"
       Depth 15
       Virtual 1024 768
   EndSubsection

   Subsection "Display"
       Depth 16
       Virtual 1024 768
   EndSubsection

   Subsection "Display"
       Depth 24
       Virtual 1024 768
   EndSubsection
EndSection

 

This is of course for a single monitor. So, we'd create another section called "Monitor2" and another section perhaps called "Screen2". As you can see from the screen section above, it points to monitor1 using the identifiers. I've not tried this, but give it a go. When you go into MCC anyway and configure the hardware for your monitor it does give you config options for Dual head config, and to configure the heads independantly. You might want to try this first, to get the correct config items in place, and then tweak/change resolution as necessary.

[coverup]

This never worked for me on my MDK 9.2 laptop. My monitor is 1280x1024 DVI flat panel and is connected to the laptop via a port replicator, my LCD is 1400x1050. What you're suggesting never worked for me (tried that many times). The main problem I believe is getting the same screen to be shown in two different resolutions. Under Windows, when I switch to the dual screen mode (clone mode), the laptop screen gets downsized to occupy a smaller area, or I can switch to a lower resolution and the screen will be of right size. Under Linux, I was never able to switch to a lower resoultion on the fly and have the screen of a right size. I always get a bigger image that does not fit the display, I think it's called panning. Of course I might be able to tweak XF86Config /xorg.conf to run it at a lower resolution and restart X, but hey I will then have to logout/login. What's the point then? Besides I am not sure you can do much if you use the proprietary ATI driver. For insatnce, you can't run it at 16bpp - it just doesn't!

 

Besides, what you're suggesting is very driver (distro?) dependent. I tried using config files which people were quoting as working fine with radeon driver under Debian or RH or Fedora, and never had any luck with them.

Edited January 24, 2006 by coverup