Help on startup error message System Fan (90)

The instructions say:
"Hold down the F1 key during the startup process and enter BIOS setup to re-enter/reset any custom BIOS settings." I would also try hitting the F1 key multiple times from the very turn on of the computer because the key may have to register at some point after turning on.

Try clearing the CMOS settings as explained on this page, it should clear out any passwords and will set the BIOS settings back to factory settings.

HP and Compaq Desktop PCs Motherboard Specifications P5LP LE Lithium

As for "The CPU fan runs normally on boot, but as soon as the Windows flash screen comes up, the CPU fan slows way down."
This is quite normal. On start-up the temperature of the CPU is not being read, when the flash screen comes up just happens to be the same time that the computer recognizes that the CPU is cold and doesn't need to be cooled.

On the "Then the installation program starts running and the CPU Fan speed starts fluctuating wildly from slow to extremely fast."
This could be normal as when files are read from a DVD the CPU doesn't work hard, but when it unpacks the files or does calculations it does work hard. Or it could be that the thermal paste between the CPU and the heat sink is not correct. Either dry , not making contact, or even too much. If the heat is not being transferred that would also explain the shut-down.

How To Fix The HP Notebook System Fan 90b Error Message On Startup?
The HP Notebook System Fan 90b Error Message On Startup indicates a serious problem which exists in relation to the heat removal process. Here, as per as HP technical support study is concerned, one of the two possible events is possible: first, the system fan is not at all spinning or even it may be the case that the system fan is not spinning properly and the second cause may be the temperature inside the case which is too high and the fan can't spin fast enough to remove the heat situation.


Steps to fix the HP Notebook fan error 90b
Step1: Working with the exterior vent
·If a user is noticing that the system fan is spinning and is blowing quite warm air from the computer, then cleaning all the exterior vents to remove dust buildup instantly by blowing air through the vent openings is necessary. This should be done while the computer is completely in "off' mode. Dust can further accumulate inside the vent opening and all around internal cooling components to prevent the heat removal process.

Step2: Perform a instant hard reset
·Performing a hard reset can further reset all the recorded thermal values in the memory by enabling you to work with the computer again even if it's only spinning for a short time to access. Save all the important files before it is in service process.

Step3: Updating the BIOS
·While updating the BIOS set-up, it may further help prevent this critical error from occurring in future as suggested by HP Notebook support
Step4: Computer servicing process

·Enable the computer service to easily clean up all the internal components and then replace the system fan carefully if necessary. Ensure that all the following items are well addressed while servicing
·Thoroughly remove all the available dust from all internal cooling components in the device.
·Ensure that wires from the system as well as from the CPU fans are well connected to the motherboard in secured mode.
·Ensure that your system fan blades are spinning correctly, and are not producing any unwanted noises. Replacing of the system fan is essential if it's not working correctly. Your above issue is now resolved completely. But do call us if you still have problem with your HP Notebooks at HP notebook Customer Support Toll-Free 1-800-213-8289 section anytime.

hi,
please insert your operating system disc in the drive and restart the computer .
Select the boot device as cd/dvd drive and save the settings in BIOS .
restart the system and boot it using the CD.

also, you can insert the disc restart the system in safe mode.
try to restore the computer using system restore.

Hi. Try this. Start up your machine and use the "Last known good configuration" entry in the list. Failing this try "Safe Mode" If you can't get into either of these them press F8 repeatedly when you start the machine. You may have to try different points in the startup for the F8 sequence to work. Select safe mode once into the black screen menu you have already seen. Assuming nothing works clean the fan out with a vacuum cleaner to help prevent overheating, put the cleaner on the fan grille and use a piece of wire to tease large clumps of dust through the fan and grille if any. Once done make sure the fan can rotate freely before trying the machine again. Assuming you get into safe mode if the machine does not work any other way you can then run system restore to set the system to an earlier date. Start, programs, accessories, system tools and system restore. I am assuming you have XP running. I have to assume quite a lot as you don't give much detail.
I hope this helps

Steve at Olive Country Computers in Spain

Hi,

This message means that the fan on your CPU (processor) is failing or has failed. This is not good because if the fan on the CPU fails your CPU will overheat and cause your machine to lock up and become non-functional till it cools down and then the same cycle will repeat till the fan is replaced.

Let me know,if needed further assistance.

Hope i helped you.

Thanks for using ' Fixya ' and have a nice day!!

Hi

Thank you for your query

You are right when the laptop first starts up it is the fan, if you are getting error message then it is the heat sink (fan on top of cpu) that will need to be replaced.

I would only recommend changing it if you know how as getting to the motherboard is quite tricky to say the least

Please dont listen to the geeks at bestbuy, they obviously dont know what they are talking about

If this has been useful please leave positive feedback/vote/testimonial - Thank you again

All computers will shut them selves off or crash when fans are failing, or have failed. Cooling fans are plugged into the motherboard, and firmware on the MB keeps track of the system fans, along with everything else. If a system fan is failing, or has failed, the signal is sent to shut down. Some PC's will shut down cleanly, others give error messages, and some just freeze up. Of course, Bad RAM, video cards, and hard drives with bad sectors, can also cause problems like you have discribed.
I would write down any error messages, and beep codes, and then look them up online for a place to start.

The problem you're describing is a classic symptom of a defective fan--some fans simply have + and - power connections. However, other fans have a third, yellow wire, for sending a pulse to the main board to tell it that the fan is indeed running. If the main board doesn't get the signal, it's internal programming instructions perform a shutdown in case of any error condition--protects the unit against excessive heat, current draw, etc. MAKE SURE THE DUST FILTER IS CLEAN! A dirty filter causes the fan to pull harder, increasing current draw, possibly triggering the symptom. The other possibility is a defective power supply causing an over-current condition. Again, the main board senses this and cues a shutdown. You'll need to send the unit out to a repair facility to confirm a diagnosis. Any reputable shop will give you a quote first with an explanation of the problem.

Your CPU fan has failed! your heatsink overheats quickly and then shuts down to protect itself from burning up. Your motherboard is Not the problem, the fan is. This fan can be replaced by any compotent laptop technician. Make sure the tech has access to Gateway or has a source that supplys Gateway parts, as the part must be made for Gateway laptops and your model exactly! 90% of this type of problem can be repaired! Don't let non-techs at Best Buy or any other dept. store tell you your PC is "No Good". Take the time like your doing and do some research the problem before giving your hard earned cash to a 16 year old "Technician/salesman/commision/bonus" person.
If the Harddrive is undamaged and it can be mounted yes, your stuff can be saved to DVD or such. Be prepared though, this type of service can be costly so ask around and get quotes.

Your CPU is overheating.

Try and get into the BIOS and increase the fan speed & any aother fan on the system. Don't increase the temperature range, as this will damage the system.

You won't be able to sort out the software problem until the system is running within the hardware limits.

You can also run a office fan to help get the system to cool while making the changes in the BIOS.