s3virge driver does not work correctly on Toshiba 490XCDT

[Graham Knap]

The Toshiba 490XCDT is a rather old laptop, featuring a Pentium II processor, i440BX chipset, and a 1024x768 LCD display driven by a 2MB S3 Virge MX. I have just installed Xubuntu 8.10 on one.

On this hardware, the s3virge driver has the following serious issues:

* It causes the LCD to flicker, much like a CRT would do at 50Hz.

* When switching to a console, the entire screen slowly turns white. Flipping back to X doesn't work.

The vesa driver works MUCH better, and doesn't even seem noticeably slower. Neither driver seems to correctly detect the LCD's native resolution; both default to 800x600, but that's easily fixed by adding the following to the "Screen" section of xorg.conf:

    DefaultDepth 16

    SubSection "Display"
        Depth 16
        Modes "1024x768" "800x600" "640x480"
    EndSubSection

The display's refresh rate is also not detected, so X assumes a Vsync range of something like 28-33KHz, and this has to be corrected to enable 1024x768 resolution. I'm not sure of what the actual correct Vsync range is for this hardware, but "30-50" worked for me (resulting in a 60Hz refresh rate at 1024x768).

(I could be mistaken, but I don't think 2MB is enough memory to do 24bpp at 1024x768 resolution.)

[Bryce Harrington (bryce)]

[This is an automated message]

Hi graham-knap,

Please attach the output of `lspci -vvnn`, and attach your /var/log/Xorg.0.log file from after reproducing this issue. If you've made any customizations to your /etc/X11/xorg.conf please attach that as well.

[Graham Knap (graham-knap)]

Sorry, I no longer have access to this machine.

[YitzchokL (yitzchok+launchpad)]

Ha! I have been struggling today with this issue on exactly this type of machine, although I'm using Hardy because I'm trying to setup UbuntuLite (it's U-Lite now but I think the version I'm installing was called that)

I couldn't shut down X either - it would crash with the white issue described above.

The VESA driver fixes my problem. I can quit X easily.

I hadn't thought of looking at Xorg.0.log - I did so and found the refresh rate settings in it. Updating xorg.conf to use those allowed me to get 1024x768 with the s3virge driver, but it had a shaky look to it - perhaps it's an interlaced mode? The Vesa setup looked better. And again with the s3virge driver I couldn't shut down X.

So I'm going back to the Vesa driver.

I'm attaching a zip file with files from the different scenarios, and the results of lspci as requested. The "low-res" files were copied after succeeding the first time with vesa so it could be that the DefaultDepth setting is not how it was, but I hope that won't matter at this point.

I hope this helps, and will be happy if you can suggest any changes which succeed in improving display quality on my machine.

[YitzchokL (yitzchok+launchpad)]

Might any of the options mentioned on the following page help?

http://linux.die.net/man/4/s3virge

[Launchpad Janitor (janitor)]

[Expired for xserver-xorg-video-s3virge (Ubuntu) because there has been no activity for 60 days.]