more lockup laptop problems with dapper

[Eric S. Johansson]

Compaq 1700t laptop  ATI Mobility Radeon 3D Hardware Graphics.

I've tried some of the suggestions I've seen posted here but none of 
them view the work.  with breezy, the laptop worked beautifully.  it was 
a joy to use but now, a minute or two after booting, it locks up at any 
to power cycle.

The messages log says nothing useful.  Just a bunch of errors from 
gconfd just before it shuts down since the server is not in use.

The only way I can keep this machine up is by booting into single user mode.

Some ideas of what I should try would be most welcome.

---eric