Help
My Laptop Model is SONY VAIO TZ33
$uname -a
Linux ubuntu 2.6.27-8-generic #1 SMP Thu Nov 6 17:33:54 UTC 2008 i686 GNU/Linux

sometimes,when the computer is starting up or shutting down,
the system crash.the indicator of CAPSLOCK and ScrLOCk kept blinking.and i cannot shut the computer down except pulling the battery out.It has happend three times.

Meanwhile I've installed windows xp.
but the same situation never occured in Xp
What can i do?