Text Problems in 7.02_EN DVD/Compiz

[Ferric.AU]

Hi, I'm running knoppix 7.0.2_EN DVD on a dell XPS 17 laptop and having a problem with garbled text. When the machine is busy (eg opening a new graphics intensive webpage) the text comes up garbled (see screenshot here). This sometimes corrects after a few seconds, or with mouseover but sometimes doesn't. It happens with all window display managers and all applications. Even the main start menu (button bottom left) is effected. I've tried running with nozram and no3d but it doesn't help. I had no problems with 6.7.2. Any suggestions re the cause or remedy? Thanks, Brad

[utu]

Greetings, Brad.
I presume you mean 6.7.1?

What kind of video/graphics are you using?
How is start button affected?
Does this happen on other sites or just this one?
Are there any background jobs going on?
All applications? even non-graphics apps?
Any electrical interference possible?
Can you verify that currently 6.7.1 doesn't have this problem?

Certainly does seem strange.

[Ferric.AU]

Greetings, Brad.
Thanks for your help.

I presume you mean 6.7.1? Yes, my mistake. I meant 6.7.1

What kind of video/graphics are you using? NVIDIA GeForce GT445M
How is start button affected? The button images are fine, but the text labels on the menu are garbled.
Does this happen on other sites or just this one? It's intermittent, but most evident on graphics heavy sites.
Are there any background jobs going on? ...Nothing major that I'm aware of.
All applications? even non-graphics apps? Yes and the default menu as well (see above).
Any electrical interference possible? It's not effected any other time
Can you verify that currently 6.7.1 doesn't have this problem? Yes 6.7 is fine.

Certainly does seem strange.

I looked around further and found this is a known problem with nouveau/cairo/xserver (there's a bit of finger pointing).

See;
http://lists.debian.org/debian-x/2012/04/msg00002.html
and
http://lists.debian.org/debian-x/2012/04/msg00049.html
and
https://bugs.freedesktop.org/show_bug.cgi?id=47266

Unfortunately trying to wind back cairo to 1.10 didn't work for me.

I might have to stick with 6.7 for a while. Esp. because Xorg only consider it medium importance

Cheers,

Brad

[Capricorny]

Maybe some hints from Klaus K re nvidia on the debian-knoppix mailing list could be of interest:

Especially NVidia chipsets are problematic. Some cards work extremely
well with the free nouveau graphics drivers, while others just cause
freezes or halt the system as soon as graphics should start up. Youd
card may be such a problem case. They are rare, though, because I did my
best to blacklist cards which are known not to work, for which the vesa
of framebuffer drivers are used again.
You could try:
knoppix xmodule=fbdev
(Card-specific framebuffer more, only the detected best resolution is supported).
fb1280x1024
(Caution: NO Knoppix at the beginning! This is the generic vesa framebuffer mode
in 1280x1024. If you like 1024x768 better, use fb1024x768 )
knoppix nocomposite no3d
(Just removes composite and 3D capabilities and use a flat 2D desktop, sometimes
a good intermediate solution which is still accelerated and allows resolution
switching)
knoppix nomodeset (or nodrm)
(Disables the accellerated modes, but most drivers won't work then and
the system will end up using vesa).

As I think many could be affected, fine if you report what you find out about solutions/lack of such

[Ferric.AU]

Maybe some hints from Klaus K re nvidia on the debian-knoppix mailing list could be of interest:



As I think many could be affected, fine if you report what you find out about solutions/lack of such

Thank-you I wasn't aware of this post by Klaus.

For me the problem seems to be only with text and matches the screenshot from this bug report, rather than a wider nvidia card issue.

In fact, I was mistaken in my last post (forgot to restart Xserver) and reverting to libcairo2_1.10 DOES seem to fix the issue.

1. download the appropriate .deb for libcairo2_1.10.2-7
   from here (ie for i386 http://snapshot.debian.org/archive/d...0.2-7_i386.deb)
2. sudo dpkg -i <the package>.deb
3. sudo service knoppix-startx stop (stops Xserver and reverts to root at prompt)
4. service knoppix-startx start

The downgrade breaks another package (libgtk2.0-cil), but otherwise seems fine after 1hr+ using iceweasel.

Good luck,

Brad

[BrokenTusk]

In fact, I was mistaken in my last post (forgot to restart Xserver) and reverting to libcairo2_1.10 DOES seem to fix the issue.

1. download the appropriate .deb for libcairo2_1.10.2-7
   from here (ie for i386 http://snapshot.debian.org/archive/d...0.2-7_i386.deb)
2. sudo dpkg -i <the package>.deb
3. sudo service knoppix-startx stop (stops Xserver and reverts to root at prompt)
4. service knoppix-startx start

The downgrade breaks another package (libgtk2.0-cil), but otherwise seems fine after 1hr+ using iceweasel.

Good luck,

Brad

This did it for me too. I'm living with the single broken package and have not yet stumbled on a bug.