Lately i have taken notice to my video turning into a bunch of horizontal lines after logging out of KDE, BB, FB, and X. I never have the problem on startup but after a while this happens when im either logging out or shutting down. this also gets carried over to the console framebuffer when im restarting while this is happening. This happens on average about 40% of the time after logging out after an extended period of time logged on. I have an ATi Radeon Xpress 200M. 128mb of memory (shared). Im not sure if it is the card not correctly dumping and refreshing its memory or if it is some other issue. I did have the ATi drivers installed but found that they really screwed up my screen in terms of icon sizes and object sizes.
an ideas on what could be wrong?

i will post a lspci -v , dmesg, and a syslog, when i get back to my laptop tomorrow.

So, with the proprietary ATI drivers it still does this ? or only with the open source ones ?

I have an old laptop with an ATI card and it did the same thing you are experiencing with the open source driver, but the problem went away when I installed the proprietary ones. (I'm not promoting proprietary drivers, just want to relate an experience, in fact I absolutely hate ATI card, they are bad quality and their drivers are also bad quality).

mainly only with the open source ones. I cannot recall if it happened any with the proprietary ATi drivers as i uninstalled them after the first day.