Comment 9 for bug 507504

I think my problem is similar.
Asus M2400N laptop with 845GM graphic chip, Kubuntu 10.04 after 9.10 upgrade. I use also
https://launchpad.net/~xorg-edgers/+archive/ppa?field.series_filter=lucid
this package.
I log in by the terminal and start up kde by startx, after some seconds the screen became black and there is a fix white underscore on the upper left corner. I can use the pc by ssh connection.
Some information on the attachment.