Weird X or monitor behaviour

mebrelith · Posted: Mon Oct 03, 2005 12:10 pm Post subject: Weird X or monitor behaviour

Ive been noticing a strange X behaviour in my box. Heres what happens:

Turn on the box - DONT turn on the monitor
Wait till more or less I think the KDM is up (my boot process takes about a minute so...)
Turn on the monitor and...
Screen seems bigger - objects and text look smaller. Log in to my desktop and same behaviour...
Reboot the computer - leaving the monitor on and when everything restarts I return to the usual size and look of things

So... any clues as to whats going on here? Maybe its some weird bug or maybe is just how it should always look and for some reason having the monitor on or off affects the X server behaviour. Take note that this is very random. Sometimes leaving the monitor off during boot wont give me the same results. Sometimes it will be normal and from time to time it will be as described above.

Also, note that Im not complaining about the small size of things. My point is: if this is how it should look then what do I have to do to make sure it happens all the time and not just randomly when I boot the box with the monitor off?

Any help in this matter shall be deeply appreciated.

EDIT: Sorry, forgot to mention that Im working with a Intel 845GV integrated video card (eats 64-128 RAM) with a screen resolution of 1280x1024. The monitor is a ViewSonic Q71-9. Latest stable gentoo-sources and Xorg-x11.
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Mebrelith Lord of Thingamajigs, Linux zealot, Gentoo advocate, KDE promoter. Linux user #373009
Omnia mutantur, nihil interit - Everything changes, nothing is truly lost.

SnarlCat · n00b Joined: 21 Sep 2005 Posts: 40

Last time I experienced issues like what you're describing I had a flakey monitor where the modelines would work at random (which, BTW, makes testing a valid modeline extremely difficult..

I'd suggest testing the monitor first.. if not that, I have no idea. \{shrug}
_________________
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Our OS who art in CPU, UNIX be thy name.
Thy programs run, thy syscalls
done, In kernel as it is in user!

mebrelith · Posted: Mon Oct 03, 2005 12:37 pm Post subject:

SnarlCat · n00b Joined: 21 Sep 2005 Posts: 40

mebrelith · Posted: Mon Oct 03, 2005 1:58 pm Post subject:

Hold everything. What is this modeline thingie? Is it something in the xorg config or what? Never seen it before. I use Xorg-x11 not Xfree86.
_________________
Mebrelith Lord of Thingamajigs, Linux zealot, Gentoo advocate, KDE promoter. Linux user #373009
Omnia mutantur, nihil interit - Everything changes, nothing is truly lost.

mebrelith · Posted: Mon Oct 03, 2005 3:50 pm Post subject:

So Ive been readin about this modeline thingie. Im not sure wether to try it or not. I mean... is it safe as houses? or will it break my box?
_________________
Mebrelith Lord of Thingamajigs, Linux zealot, Gentoo advocate, KDE promoter. Linux user #373009
Omnia mutantur, nihil interit - Everything changes, nothing is truly lost.

SnarlCat · n00b Joined: 21 Sep 2005 Posts: 40

A 'modeline' is what X uses to describe the screen.. data points for resolution, starting locations, etc for both the X- and Y-axis..

While you generally don't see them in the config files, they're still used; check out the /var/log/Xorg.0.log (or something similar).. you'll see them in there if you look carefully..

In general, editing a modeline is totally unnessary in these modern times; there was a time when it became necessary to support different hardware (especially the failing kind, like what I had..)...

My guess is that you have either a bad (or going bad) monitor, or a video card that is confused...

I am, however, not an expert in this.. hopefully others can offer additional insight..

As for it's 'safe'-ness, it depends what you do.. you can make it start drawing off your screen (fairly harmless), and you can make it try to refresh too fast (um.. don't touch my monitor).. it depends what you do.. that's why, in general, I say leave them alone..
_________________
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Our OS who art in CPU, UNIX be thy name.
Thy programs run, thy syscalls
done, In kernel as it is in user!

phsdv · Guru Joined: 13 Mar 2005 Posts: 372 Location: Europe

Modern video cards and monitors do talk with each other using the DDC protocol. X11 supports this. In this way your OS can now what video modes your monitor supports. Now when you do not have your monitor switched on at the moment X11 starts, this information can not be read! Look in your Xorg.log file. Or even better save the 2 versions of this log file, one with monitor switched on an one without and do a diff between the 2.