System is an IBM netvista 6578-LBU with onboard i815 video. Just about any
system activity including video update and disk activity causes a momentary
loss of video sync with an extremely annoying video flicker.
disabling dri module didn't help (Xconfigurator --nodri)
The i815 is completely unsupported in XFree86-4.0.1a as shipped with
Guinness, and is still unsupported in XFree86-4.0.2 as currently shipped
in our latest rawhide packages.
You can try the latest rawhide out anyway to see if it works by coincidence,
as it is likely similar to i810, or you can try out the latest XFree86
experimental code by checking out the code from XFree86 CVS yourself and
building it. Instructions for doing so on http://www.xfree86.org
Hopefully this card will be supported in the future.