Same with P4B266 on Dapper 686. I found a solution ther :
http://forum.ubuntu-fr.org/viewtopic.php?id=42873
sudo gedit /boot/grub/menu.lst
add *acpi=force* to :
kernel /vmlinuz-2.6.15-23-k7 root=/dev/hde2 ro vga=792 quiet splash
to have :
kernel /vmlinuz-2.6.15-23-k7 root=/dev/hde2 ro vga=792 quiet splash acpi=force
Same with P4B266 on Dapper 686. I found a solution ther :
http:// forum.ubuntu- fr.org/ viewtopic. php?id= 42873
sudo gedit /boot/grub/menu.lst
add *acpi=force* to :
kernel /vmlinuz- 2.6.15- 23-k7 root=/dev/hde2 ro vga=792 quiet splash
to have :
kernel /vmlinuz- 2.6.15- 23-k7 root=/dev/hde2 ro vga=792 quiet splash acpi=force