If reseating the fan plug does not help.
What you may have is a fan that is a little worn and slow to start.
The result is when the bios does it's scan the rpm's are too low......error.
When you open the case and look at the fan it is now up to speed.....looks good.
The fix......replace the fan.
Hi, I have a wierd problem with my HP Desktop. It's a Pavilion a1747c, running an AMD 64 dual processor with 3 Gigs of ram. I am running Windows Vista Home Premium. Lately on boot, I receive a notice that the system fan has failed and to press F2 to ignore. The system then boots normally. I keep all vents clean and blow dust out of the Mother board at least every Month or so. Both internal fans are running normally and they are quiet. Is there a way to clear the message? I have never had a shutdown because of heat. Thanks.

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