[SOLVED] Laptop with dead screen. Cannot get external monitor working under X. Slack 13.37
SlackwareThis Forum is for the discussion of Slackware Linux.
Welcome to LinuxQuestions.org, a friendly and active Linux Community.
You are currently viewing LQ as a guest. By joining our community you will have the ability to post topics, receive our newsletter, use the advanced search, subscribe to threads and access many other special features. Registration is quick, simple and absolutely free. Join our community today!
Note that registered members see fewer ads, and ContentLink is completely disabled once you log in.
Laptop with dead screen. Cannot get external monitor working under X. Slack 13.37
well here we go. So my main desktop is down with dodgy mobo which I have sent back under warranty. So in the mean time I have dug out the old Panasonic CF-T1 with a dead 12 TFT flat panel. With the aid of an external monitor (View Sonic 24" LCD" I installed Slack 13.37 ok. BUT on boot up it starts to go through the boot procedure, text whizzes by as it does it's stuff and latter in the boot process it must switch to some other video mode as it attempts to go full screen and then all I get is a flashing grey fuzz.
I have my default runlevel set at 3 so from my understanding 'X' should not come into the equatition at this time.
I don't really understand what it causing the attempted mode switch half way through the boot up procedure and messing up my screen. If I could just get something up at any resolution then I can take things from there.
I have tried changing lilo settings to
vga = normal - result same
vga = 791 (and others) - result same
Unless I am wrong, let's forget 'X' for the moment and try to get a usuable console.
The "nomodeset" might cause problems with running X but I am not knowledgeable enough to say for sure (but at least you have the console you wanted ).
I have found the kernel in 13.37 rather unimpressive myself. I am experimenting with the pre-compiled kernel from "current" - but you need to upgrade to the "current" version of lilo as well. This might be a work around for you too.
KMS is required to run X, but the 'nomodeset' option disables this. My googling suggests your Panasonic CT-F1 has the Intel 855GM graphics chipset. You could try disabling the defunct TFT panel display with:
Thanks for all the replies. Allend I did try your lilo append line but then I was back to an unusable console. So it seems I can have a console (init 3) or graphical login (init 4) but not both :-(
So as a work around I took out the 'nomodeset' option from lilo, set inittab to boot into X, disabled the duff built in screen via the bios and removed my xorg.conf altogether.
On boot I get an initial readable screen then it goes into gibberish mode as KSM kicks in then just sit patiently and eventually gets me to KDM login screen. O.K the resolutions all wrong but I can work on that latter. HOWEVER, of course, there needs to be an however, as KDM finishes the login routine KDE just completely crashes out leaving the screen blank, ('no signal' my screen reports, will start a new thread for this one). So as a stop gap I am using wmaker window manager.
Although things are not perfect, as I can at least now get to a graphical U.I I will mark this one as 'solved', kind of.
Thanks again for all the tips and suggestions, BashTin.
Regardless of your chipset (though it seems more common with intel), if KDE
crashes on startup, try disabling the Composite extension (which will also
disable all of the fancy desktop effects). Place the following content in
a file at /etc/X11/xorg.conf.d/disable-composite.conf:
Option "Composite" "Disable"
As to the garbled display when KMS kicks in, did you try psion10's suggestion of specifying the video resolution with a line like
Thanks again. So another couple of steps in the right direction. Composite disable gets me into KDE. Also had another look at Psion10's lilo command and added video=LVDS-1:d which got rid of the onboard panel. I thought that disabling the panel in the bios would do it but it somehow remained active. I think the problem with the resolution was that X was using the resolution for the laptop display and simply mirroring that display to the external one, hence the reduced resolution. Having definitely disabled at last the on board screen it seems X is now forced to use the external panel and configure it correctly. So I have 1920x1080, HOWEVER, the screen flickers very badly and I have a kind of double image flashing on and off across the screen. I am beginning to wonder if perhaps it is a intel driver issue (perhaps update drivers) or whether my lowly 866mhz Pentium III CPU and onboard Intel graphics chip is upto to the job? Any more ideas and a big thanks of course for getting me this far.
PS. I know that in xorg.conf you can specify two screens, a server layout, etc but last time I tried that route I just seemed to get into a bit of a mess and found things worked as they should just by letting X do probe for the monitors and settings. Might have another crack latter.
PPS: No matter what I seem to add to lilo.conf the console still gets garbled.
Try setting a maximum resolution of 1280x1024 in KDE using System Settings -> Display and Monitor -> Size and Orientation and see whether the screen appearance improves. I suspect a resolution of 1920x1080 is too big of an ask on your hardware.
Thanks again Allend, appreciate the research you have been doing. However, still in the same situation. Nothing works for the console (except nomodeset of course).
I can only get the resolution stable at 1024x768. Interesting to note that this stable 1024x768 is with the dead screen enabled. If I disable this dead screen all resolutions, including 1024x768, flash double images. Obviously a clue there somewhere.
So it seems that with the dead screen active X chooses the highest resolution common to both and sets both screens to this (1024x768). Just don't know why it seems to mess up configuring/driving the external screen without the 'aid' of the dead built in screen (yes tried mode lines, xrandr, xorg.conf.....).
Anyway, happy to leave it at this for the mo as I could play around with this for another week and still get no where. As I said at the beginning this is only a stop gap until I get my desktop back up. Also this lowly machine is not really capable of running KDE (I've tried) so now exploring the joys of Window Maker.
Good luck with WindowMaker! It is a better fit for your hardware. I am using it again on my netbook, which has involved a big time input to do the tweaks that I wanted, but I am very happy with the result.
It would be interesting to know whether Slackware 14 would work better for you. KMS and Intel graphics support seems to have become better since Slackware 13.37 was released.