I suspect the cpu is overheating, even with the fan.  If you hear the fan on all the time, it suggests that it never cools down enough NOT to need the fan.  Is the fan blocked in any way?  If you use the laptop on your lap or place it on your sofa for example, your clothing or sofa cushions will restrict the airflow.  Use it on a desk or a lapboard, some are available now with extra fans as well.  You can download a free cpu temperature monitor (just do a web search for cpu temperature monitor) and check the cpu temperature frequently - some monitors will provide warnings when the temperature exceeds some preset limit.
Paul Hachmeyer      
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From: Personal Computer Hardware discussion List [[log in to unmask]] On Behalf Of [log in to unmask] [[log in to unmask]]
Sent: Thursday, August 06, 2009 2:55 PM
To: [log in to unmask]
Subject: [PCBUILD] Toshiba Laptop is turning itself off.

Hi!
My Toshiba Laptop is turning itself off.? I do have a fan going at all times to keep it cool so I don't believe that's the problem.? Any suggestions or ideas would be greatly appreciated.
Thanks in advance for your time.
L Bruzas
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