I am working on a Dell Dimension 2300. I have installed a new cpu fan and shroud. The fan is spinning. I have cleared the event log... Yet I still get an alert: cpu fan not detected when I boot up. How can I fix this?
This Question has been solved and asker verified All Experts Exchange premium technology solutions are available to subscription members.
Experts Exchange has been collecting answers to technology questions since 1996…3 million and counting! If you have a question, chances are we already have your answer.
If you can't find the exact answer you're looking for, ask our exclusive community of 50,000 experts. You’ll get a personalized answer from a trusted professional.
Thousands of free tech tips, tricks, how-to’s and tutorials are available in our peer reviewed articles section. See for yourself how smart our experts are, no login required.
Save solutions to your questions, answers you’ve discovered through searching plus helpful articles in your personal knowledgebase for easy future access.
Access the answers to your technology questions today.
30-day free trial. Register in 60 seconds.
Members of the expert community talk about why the experience at Experts Exchange is different than what you will find anywhere else.
Try it out and discover for yourself.
30-day free trial. Register in 60 seconds.
Join the community of experts here and help other tech pros by answering question in your area of expertise. You can earn FREE access to all Experts Exchange's premium features and resources.
Thanks. I'm sure that it is the fan connection because that is where the old fan was removed, and it is also shown on Dell's diagram. I've read that "I could remove heat sink and fan, clean cpu and heat sink with solvent, apply Quick Silver or other heat transfer grease (per directions) and reinstall. Be careful not to damage the CPU" I think I will try it at some point. Maybe this evening. But I'm sure open to any other suggestions!!!
In the BIOS...light up the Num Lock, Caps Lock, & Scroll Lock keys on your keyboard (they all should be lit green) and while holding down the ALT key, hit E (i.e. ALT-E). The PC should beep once...now hit ALT-B to save changes and reboot. If this does not work then try pulling the jumper on the system board that says either: CLR_EISA or CLR_NVRAM.
Thanks smiffy13. I followed your instructions (num lock, cap lock, & scroll lock on lit green) Alt+E (Got no beep). And it didn't correct the fan not detected message. I couldn't find clr-eisa or clr-nvram on the motherborad. I did change the jumpers and clear CMOS. No change. The fan is spinning; the computer is working just fine. But still that pesky message.
I've looked and looked for that one. There is a place to clear the event log, and to verify the log has been read (which also clears the log.) I've done that. But a new warning is generated the next time I boot up. Nope, there is no option to disable the warning in the BIOS.
Yes, it is only a bootup warning - no further alerts or warnings after the computer is booted up.
Straight from Dell documentation for this error;
"CPU fan not detected
The microprocessor fan cable is not plugged in or is defective.
Ensure that the microprocessor fan is connected to the fan connector on the system board."
Thats all they give on the subject and there is no setting in bios as far asI can see in their docs.
Well, if the fan's spinning fine, then, as I noted before, "...either the motherboard sensor isn't working or the fan isn't transmitting the rotational data"
The only way to confirm that would be to try another HSF -- you could actually do that without replacing the heatsink (plug the "real" installed one into another fan connector so it will get power; plug the 2nd one into the CPU fan connector and just "hold it" in place. Turn on the PC. See if you still get the warning.
This would at least tell you if its the sending unit on the fan, or the sensor on the motherboard. Not sure you'd do anything different than just tell your friend to "live with it" -- but if it's just the fan you might want to replace it with a functioning unit.
Business Accounts
Answer for Membership
by: CallandorPosted on 2005-10-18 at 12:37:07ID: 15110714
You have to make sure the cpu fan is plugged into the right header on the motherboard - it should be labelled "cpu". The fan sensor for the cpu uses this header.