My first thought is that their was a one time error in getting the 
message. I would consider three options:

Keep using the computer and see if it happens again.
Keep using the computer for a while with the case cover off and 
physically check the fan operation if the message reoccurs.
Replace the fan. Unless it is a unique fan, it is only a few dollars, 
fairly easy to replace and gives peace of mind.

Tom


Donald DeWitt wrote:
> Hello everyone,
>
> I have a 4.5 year old Dell Dimension 8400 running XP. When I turned on the
> computer this morning there was a message at the top of a black screen: CPU
> fan failure. Press f1 to continue or press f2 for setup. By pressing f1 the
> computer continues to boot up normally. Opening up the computer and doing a
> close-up inspection, the fan seems to be working normal, (that is no unusual
> sounds or vibrations). The computer also undergoes a thorough cleaning
> inside and out two times a year and it is located in an air-conditioned
> environment.
>
> Question: what should I be doing now to confirm that in fact there is a fan
> problem?
>
> Don DeWitt
>
>            
>
>   

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