Salix 13.1.2 works perfectly with ATI Mobility Radeon 4200 HD video if you pass nomodeset in the boot line; plus a recap of what works/doesn't with this video chip

What nearly killed me in Fedora 13 and 14, wounded me grievously in Ubuntu 10.10 and not bothered me at all in Debian Squeeze is entirely manageable in the Slackware-based Salix 13.1.2. What the hell am I talking about? I have a working display in Salix 13.1.2 on my Lenovo G555 laptop, which features an ATI Mobility Radeon 4200 HD video chip that kernel mode setting has left behind.

I downloaded, burned and booted from the Salix 13.1.2 live CD, added nomodeset to the boot line and soon found myself in the Xfce-based Salix desktop with perfectly working video. I'm not 100 percent confident in the process as this is my first time doing this in Salix, and things are a bit different than in Fedora and Ubuntu, both in how it's done and the fact that it actually works.

This is how it's supposed to work. Either nomodeset or, in my case, radeon.modeset=0 in the boot line (entered during boot time or in the GRUB configuration) should allow this particular video card to not be blurry and wavy in the framebuffer and graphical (Xorg) display.

Since this doesn't work in the most recent Ubuntu release and Fedora 13 and 14 with 2.6.34+ kernels, there is more afoot. It could be the boot sequence, i.e. when and how kernel mode setting and initialization of the display happens during startup.

Another way to "solve" this problem is by using the proprietary video driver, which in the case of ATI video cards/chips is the fglrx/Catalyst driver available directly from AMD/ATI, packaged up by such distributions as Ubuntu and kept in a non-free repository, or in the case of Fedora, and very recently and only for Fedora 13 at this point, offered in the RPM Fusion repository (a must-have for Fedora users who like multimedia).

This often works because the fglrx/Catalyst driver cannot use kernel mode setting (aka KMS), so this should theoretically work with video chips such as mine. This is true in Ubuntu 10.10 and Fedora 13 but not in Fedora 14. And I'd rather stick with the open-source driver anyway. It's faster (in my case anyway), more reliable and always updated with the rest of the distribution through the built-in package-management tools.

What this successful test of Salix 13.1.2 means is that in all likelihood Zenwalk and Slackware itself will also work on my machine with nomodeset in the boot line. When I was having this same problem with the Intel video driver, eventually Ubuntu could figure out that my Intel chip (82830 CGC) couldn't do KMS and automatically turned it off — a great thing for potential Linux users who haven't been through as much $#%^ as many of us have.

So here's the Lenovo G555 / ATI Mobility Radeon 4200 HD scorecard thus far:

Ubuntu 10.04 (2.6.32)
standard boot: works

Ubuntu 10.10 (2.6.35)
standard boot: wavy, blurry
nomodeset: wavy, blurry
radeon.modeset=0: wavy, blurry
Ubuntu's fglrx package: works

Fedora 13 (2.6.33 kernel)
standard boot: works

Fedora 13 (2.6.34 kernel)
standard boot: wavy, blurry
nomodeset: wavy, blurry
radeon.modeset=0: wavy blurry
RPM Fusion fglrx: Finally updated for latest 2.6.34 kernel, not tested
ATI/AMD's fglrx/Catalyst script: works

Fedora 14
standard boot: wavy, blurry
nomodeset: wavy, blurry
radeon.modeset=0: wavy, blurry except VERY occasionally (randomly 1 out of 20 boots)
RPM Fusion fglrx: unavailable
ATI/AMD's fglrx/Catalyst script: no video at all

Debian Squeeze (2.6.32 kernel)
standard boot: works

Salix 13.1.2 (2.6.33.4 kernel)
standard boot: wavy, blurry
nomodeset: works