Dell mini 10 Z520 GMA 500 Ubuntu 9.04 kernel 2.6.28-14 freeze

Update for the dell mini 10 installation:
With the latest update to the kernel 2.6.28-14, the graphic is broken, you can't log in unless in safe mode. Solution:
2.6.28-14 kills PSB driver on Dell Mini 10 & Acer One 751h

sudo apt-get install psb-kernel-source
sudo shutdown -r now

the psb kernel will be automatically recompiled.
Enjoy!

If you are experiencing freezes (you can move just the mouse), this should fix it:

sudo apt-get update
sudo apt-get install poulsbo-driver-2d poulsbo-driver-3d psb-firmware

sudo nano /etc/X11/xorg.conf
Section "Device"
Identifier "Configured Video Device"
Option "AccelMethod" "EXA"
Option "DRI" "off"
Option "MigrationHeuristic" "greedy"
EndSection

ctrl-X save &restart