I have the same problem on my Acer Travelmate 4220 after a clean install of 10.04 32bit. As a workaround, try to disable the power manager at system->preferences->startup applications.
I have the same problem on my Acer Travelmate 4220 after a clean install of 10.04 32bit. As a workaround, try to disable the power manager at system- >preferences- >startup applications.