My fan on my computer has had a loud intermittent fan noise. I dusted and it was less frequent, but still happened. Lately it's been more frequent.

Today my computer just SHUT down on it's own. I had not been getting any error messages. I dusted again and tried to restart.

It starts, beeps once (like normal) and gets to the screen where it tests memory and has the F2 and F8 safe mode options. It just freezes there and nothing happens if I push F2 or F8.

Please help. I forgot to mention what kind of setup I have. It is a desktop computer with Windows XP.Bjay100, there are a number of fans in your PC,....... are you refering to the power supply fan that blows out the back of your PC?....If this is the fan which was making the noise you may need a new power supply, this noise may have been the bearings going bad.......swap in ANOTHER KNOWN good PS and see if that fixes your problem, ..... go to youtube and search for "changing power supply" if you are unsure of how to do it.Run memtest: http://www.techspot.com/vb/topic62524.html
I changed the power source and it started!

But then when I restarted it later, it froze again. I turned it off and on, and it BOOTED just fine. What could cause that?

Power source or power supply?........ Reseat your memory ........See if it responds......then run the memory test (Reply # 3) if you can.Comrade,I dont see any connection related with ur computer freezing and the fan.If u are using a sata Hdd,have u checked ur sata CABLE.Have ur sata cable cheked once.