Xorg vesa driver stopped working after kernel upgrade

[Salvo Isaja <salvois@users.sourceforge.net>]

Hi there,
I'm a firstposter, hope this is the right place to ask.
Excuse me if I'm verbose, I hope too much is better than too few.

I use Debian for a few years now (since Sarge was Testing), the Testing 
distribution, regularly dist-upgrading it. I have an ATI Radeon X1300 
graphics card, hence "vesa" driver in Xorg ("ati" and "radeon" don't 
seem to work, will look into the proprietary ATI driver in the near 
future). FWIW, I have an AMD Sempron PC, 512 MiB RAM, 1152x864x24bpp 
screen mode.

All worked just fine on this box until a kernel update in Testing after 
Etch, and it just works if I stuck with linux-image 2.6.18 486. With 
later kernels (was it since 2.6.22?) when X starts it shows a black 
screen, with a red pattern on top of the screen (depending on the screen 
resolution, other patterns at 1024x768 for example, seems garbage from 
console).

I'd say all my system is aligned with the current Testing distribution 
except linux, and since later kernels support my USB wireless dongle, 
I'm trying to keep the pace. I have installed just the basic linux-image 
package, with no console framebuffer, logos and the like.

Any suggestion?
Thanks,
   Salvo
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