This could be caused by overheating. Check the external fans operation 
and dust conditions. If there is a case filter, remove and clean it. 
Being careful of static electricity, open the case and check for 
internal fan operation and dust conditions and check heat sinks for dust.

If the computer is excessively dusty, there are sites on the Internet 
with directions on cleaning the internals. The concerns are static 
electricity and over spinning the fans. Make sure the cable connections 
are secure when you are done.

I hope this helps.

Tom Mayer

Barbara Crocker wrote:
> Dear friends,
>   
>> Our HP Pavilion shuts down in the middle of an
>> operation and when we try to turn it on again, we have
>> to unplug it from the back of the tower to get it to
>> power up again.  Is this a minor problem that we can
>> fix or is it expensive to repair?
>>
>> Thanks!
>>
>> Barbara Crocker 
>>
>>
>>     
>
>
>
>   

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