Incorrect Projector screen size

[dj_bridges]

Have just bought a projector (Optoma DS316L DLP) for watching films at home from my laptop (spec in signature). When I turn on and connect the projector, the laptop finds it and asks if I want to review the settings for the new display. Unfortunately none of the options for the VGA output (in Configure Your Desktop > Hardware > Display and Monitor > Size & Orientation) give a full-screen on the projector. The only options are 1024 x 768, 800 x 600 and 640 x 480. My LVDS1 screen is set to 1280 x 800 so am guessing the projector needs to be at least this size. It also makes the LVDS1 screen on my laptop very flaky e.g. it often blanks out and desktop plasma widgets are moved all over the shop.

I have had problems before when connecting to projectors, but have only had to do it very rarely. It is frustrating that Windows works perfectly when connecting to a projector. Am sure Linux can do it - the question is how?

Anyone got any suggestions??

[pags]

A projector is like another monitor (separate from whatever else you may have connected), so it's settings are not dependent, for example, on the LVDS (laptop LCD) settings, etc.

You want to focus your efforts on the VGA settings, only.  If you're using this for movies, etc (especially if you're running with the lid closed), you probably want to disable the LVDS, and run the VGA only.

I little quick search leads me to believe that this projector's native resolution is 800x600 (they are like LCD monitors, in this way...they have a resolution they work best at...this is because they actually have little LCDs inside them to produce the image), so you should set that as your resolution for it.  You may need to adjust the refresh, etc (but that's not been an issue for me, in the past).

Another option may be to set it up through PCC, where you can select the monitor type...

[dj_bridges]

pags, thanks for your reply.

I had assumed that all I needed to change were the VGA settings, but have found in the past that changing the LVDS or VGA often affects the screen view on the other - hence my plasmoids getting shifted all around the screen. I take it this shouldn't be happening from your post?

Will try setting it up through PCC in case there are some other issues. Good to know the native resolution is 800 x 600 - thanks for that!

[ff103]

I use a projector regularly for training using PCLOS and I have found that the highest res the projector will accept is 1024x768. I run my laptop at 1280, but whenever I teach a class and use the projector, I have to change it to 1024. hope this helps. 

[pags]

I use a projector regularly for training using PCLOS and I have found that the highest res the projector will accept is 1024x768. I run my laptop at 1280, but whenever I teach a class and use the projector, I have to change it to 1024. hope this helps. 

This would particularly be the issue when the display is duplicated on both (which is what I presume we're aiming for, here...myself, with dual-monitors, I want separate desktops on each one ).  This can also vary, depending on chipset and driver. In some cases, the projector will show a small subset of the other screen (when they're set to different resolutions).  The can be useful during presentations, as it gives you an "off-screen" area to prep, etc., before dragging it into view where everyone can see it.

If you're running KDE, it has pretty good tools for setting up the display hardware (for the current user/session).  PCC is much better suited to system-wide changes/other DEs/KDE failures, etc...
 

[dj_bridges]

Thanks for all the replies. Sorry for not testing this earlier, but it appears that the LVDS and VGA output are intimately linked. The only way that I can get the projector to project the entire screen area is to change the LVDS res to 800 x 600 and set the VGA to the same. Obviously this means that the laptop screen is sub-optimal. Have tried changing every possible option in the configuration menu, but no luck.....

There must be a way to do this, but it is far from obvious / intuitive. Any other ideas??

[pags]

How have you tried setting up the display(s)?

Have you gone into the KDE Control Centre (Configure Your Desktop) > Hardware > Display and Monitor > Size & Orientation?

One of the displays there (presuming they both show up) should have multiple choices under "Position".  Have you tried changing it. along with setting the resolution of the appropriate display (if left as "Clone of", the the resolutions have to match, IIRC...)

[dj_bridges]

pags - sorry if I wasn't clear. I have changed every conceivable setting / combination in the Control Centre. For example if I leave the LVDS settings as they should be set the VGA to the projectors native resolution (800 x 600) and position it to the Left  or right then it merely cuts off the screen to that direction on the VGA e.g. if position is set to the left then the left hand side of the desktop is cut off on the VGA output. Setting the screen position as absolute also doesn't help things.

One thing which really puzzles me is if you press 'Identify Outputs', my understanding would be that a message box saying LVDS should show up on the laptop and one saying VGA pops up on the VGA. This doesn't happen - instead both outputs show both messages (usually with one overlaid on the other). This again seems to suggest that the two outputs are somehow one and can't be seperated...

Wish I could understand this - it is a bit embarrassing fiddling around with multiple settings at a meeting to give a presentation on a projector, when a Windows machine does it without any user input.

[pags]

That is how "Identify Outputs" should behave.  They will overlap when the display is "Cloned".  That seems to indicate that PCLOS does recognize them as distinct entities.

What is your chipset?  Try (the bolded part):

[jpaglia@gx620 ~]$ lspci | grep -i vga
00:02.0 VGA compatible controller: Intel Corporation 82945G/GZ Integrated Graphics Controller (rev 02)
[jpaglia@gx620 ~]$

from a terminal.

Also what driver is being used?  If it's an onboard chipset, there maybe the chance to allocate more memory to it (depending on how much you have).  lack of display memory could be giving you issue, also.

[dj_bridges]

pags appreciate you helping me out with this. The output from lspci is:

00:02.0 VGA compatible controller: Intel Corporation Mobile GM965/GL960 Integrated Graphics Controller (primary) (rev 03)

Which I believe is an onboard chipset. Not sure how I can allocate more memory, but am willing to try anything.

What is weird about the 'Identify Outputs' is that they overlap whether the display is cloned, or absolute. I expected them to overlap when one is a clone of the other, but not when there is no clone. Perhaps I just don't understand what 'Identify outputs' is meant to achieved - I thought it would enable one to define that the laptop screen is the LVDS (by flashing up LVDS exclusively on the laptop screen) and that the projector was VGA....

[pags]

pags appreciate you helping me out with this. The output from lspci is:

00:02.0 VGA compatible controller: Intel Corporation Mobile GM965/GL960 Integrated Graphics Controller (primary) (rev 03)

Which I believe is an onboard chipset. Not sure how I can allocate more memory, but am willing to try anything.

What is weird about the 'Identify Outputs' is that they overlap whether the display is cloned, or absolute. I expected them to overlap when one is a clone of the other, but not when there is no clone. Perhaps I just don't understand what 'Identify outputs' is meant to achieved - I thought it would enable one to define that the laptop screen is the LVDS (by flashing up LVDS exclusively on the laptop screen) and that the projector was VGA....

That looks like the same chipset I'm using, and it's working here...

Can you post the output of xrandr?

Mine looks like this:

Code: [Select]

[jpaglia@core2pclinux ~]$ xrandr
Screen 0: minimum 320 x 200, current 2560 x 1024, maximum 4096 x 4096
LVDS1 connected (normal left inverted right x axis y axis)
   1400x1050      60.0 +   60.0
   1280x1024      60.0
   1280x960       60.0
   1024x768       60.0
   800x600        60.3
   640x480        59.9
VGA1 connected 1280x1024+0+0 (normal left inverted right x axis y axis) 338mm x 270mm
   1280x1024      60.0*+   75.0
   1280x960       75.0
   1152x864       75.0
   1024x768       75.1     70.1     60.0
   832x624        74.6
   800x600        72.2     75.0     60.3     56.2
   640x480        72.8     75.0     66.7     60.0
   720x400        70.1
DVI1 connected 1280x1024+1280+0 (normal left inverted right x axis y axis) 376mm x 301mm
   1280x1024      60.0*+   75.0
   1280x960       60.0
   1152x864       75.0
   1024x768       75.1     70.1     60.0
   832x624        74.6
   800x600        72.2     75.0     60.3     56.2
   640x480        72.8     75.0     66.7     60.0
   720x400        70.1
TV1 unknown connection (normal left inverted right x axis y axis)
   848x480        30.0 +
   640x480        30.0 +
   1024x768       30.0
   800x600        30.0
[jpaglia@core2pclinux ~]$
Note: My laptop is currently docked, with the lid closed.  The docking station has both VGA and DVI connectors, each with a 1280x1024 LCD monitor attached, with my desktop spanning both monitors (for a total area of 2560x1024).  There are limitations, IIRC, for the Intel chipset.  DRI can only function within a 2048x2048 space, so I have to disable KWIN effects for this setup.  I also think there is a 4096x4096 overall limit.

let me check memory allocation...

...

Need to do a little more research on the memory part...will post this and check back.

EDIT:
Check the memory allocated with dmesg | grep agp:

Code: [Select]

[jpaglia@core2pclinux ~]$ dmesg | grep agp
Linux agpgart interface v0.103
agpgart-intel 0000:00:00.0: Intel 945GM Chipset
agpgart-intel 0000:00:00.0: detected gtt size: 262144K total, 262144K mappable
agpgart-intel 0000:00:00.0: detected 8192K stolen memory
agpgart-intel 0000:00:00.0: AGP aperture is 256M @ 0xd0000000
[jpaglia@core2pclinux ~]$
Here, you can see 8Mb were allocated

agpgart-intel 0000:00:00.0: detected 8192K stolen memory

[dj_bridges]

pags thanks for the reply.

Ok this what xrandr gives when I have the VGA connected at 800 x 600:

Code: [Select]

Screen 0: minimum 320 x 200, current 1280 x 800, maximum 8192 x 8192
LVDS1 connected 1280x800+0+0 (normal left inverted right x axis y axis) 331mm x 207mm
   1280x800       60.0*+   60.0*
   1280x800_60    60.0
   1024x768       60.0
   800x600        60.3
   640x480        59.9
VGA1 connected 800x600+0+0 (normal left inverted right x axis y axis) 0mm x 0mm
   1024x768       60.0
   800x600        60.3*    56.2
   848x480        60.0
   640x480        59.9
TV1 unknown connection (normal left inverted right x axis y axis)
   848x480        30.0 +
   640x480        30.0 +
   1024x768       30.0
   800x600        30.0
Output from dmesg is:

Code: [Select]

Linux agpgart interface v0.103
agpgart-intel 0000:00:00.0: Intel 965GM Chipset
agpgart-intel 0000:00:00.0: detected gtt size: 524288K total, 262144K mappable
agpgart-intel 0000:00:00.0: detected 8192K stolen memory
agpgart-intel 0000:00:00.0: AGP aperture is 256M @ 0xc0000000
So looks like we have the same amount of memory allocated.

With the above settings I am only getting a square of the top left hand side of the screen (about a third of the right hand side and bottom of the screen is missing)...

[pags]

OK.

We can try to set the displays with xrandr.  I'm not in a position to check the syntax at this time, but I'll post some directions soon...

[dj_bridges]

pags - ready to try anything!!! Once again thanks for taking the time to help me out with this 

[pags]

Sorry about the delay...weekend at home...

I'll be back at work tomorrow, and I'll have additional monitors to test with, after which I'll post the commands...