cpu fan turning on and off too frequently

Dear Board,
I am not worthy of this place and while I have a little knowledge of computers I could not dance in your shoes.

Situation -- Fan at the back of my HP very near the bottom comes on and off very frequently. It will turn on full speed for about 30 seconds then stop then half speed for 3 seconds then stop, then turn on for 10 seconds and stop. I think you get the drift. I think it is the CPU Heat Sink Fan. Could it be the Video Card Fan, if it even has one. I haven't taken it apart because I just moved and my brother while helping me move asked to borrow my tools so I don't even have a screwdriver to open it up to identify the fan and its reason for turning on to begin with. the on and off every 15 seconds or every 5 seconds depending I do know is not healthy nor is it functioning properly. I read a couple of messages and none of them specifically handle or even really come close to discussing my problem, but then again this site is super cool and I probably missed it if it is here. Thanks so much in advance for any help you guys/girls can provide. Michael B. :-o

 

Laptop or desktop?
My old HP laptop fan comes on more than it used to, simply because I'm too scared to disassemble it and clean out the inside.
I believe on a desktop, the CPU fan is supposed to run constantly otherwise the CPU overheats and the computer shuts down.

 

This reads like it's the video card in a tower, check that by looking to see whether the cable to your monitor is connected next to it. If it was the CPU fan, it would normally be around halfway, or higher up the tower.

 

Do you have variable ("smart") fan speed enabled in the system BIOS?

If so, the CPU cooler (and possibly other) fans will automatically speed up/slow down based on the system temperature and/or processor usage.

This being said, if you suspect one or more fans aren't working properly (squeaking, clicking or not spinning at all), err on the side of caution and replace them. A few bucks for a fan beats a system meltdown.

 

ok. Thanks. I am going to get my brother over here to check out the video card. However if it is the Video Card Fan, then will I have to replace the Video Card or does the fan disassemble. Or do I have to buy a new Video Card. Also Would there be symptoms related to the Video Card that would effect the computer. Something that I would recognize. Thanks for your help I can't tell you enough that sites like this are a god send to the computer illiterate. I will let you know in a couple of days what the fan is linked to; whether it is the cpu or the video card. Thanks again mike...

Also is there a way to get in touch with an administrator I would like to contribute to the site. Mike B.

 

How would i check my BIOS to see if that in fact was the reason that the fan is in fact going from hi to low to medium to low to hi to low to medium. Please if you know how give me the instructions on how to check my BIOS. Mike Thank You.

 

:waveThis site is so cool. All of you deserve something for all the great advice that you dispense

 

• Start the PC. Immediately hit the "Setup" or "BIOS" key (usually "DEL").
  
• The BIOS setup screen will pop up (Careful! If you're not sure what changing a setting does, don't change it. If you accidentally mess up you can reboot, re-enter the BIOS and choose "Restore Default Settings").
  
• Tab through the screens (the exact location or screen will vary based on the model). Look for the term "Smart Fan" (or possibly Thermal Management). If Smart Fan shows as "enabled", the BIOS automatically adjusts the speed of the CPU fan (and possibly the video card fan) based on the system temperature and processor usage.

Depending on the fan size, you can sometimes order an aftermarket replacement from Newegg or CompUSA (measure carefully; one size does not fit all).

Also consider the age and performance of the current video card against the cost of a new one. If you have an older or entry-level PCI-e slot card (check the system specs or the label on the current card), decent cards (1GB DDR3) can be found for less than $50 after rebate. If you replace the card, I would suggest sticking with the same video chipset mfr. (ATI or NVIDIA) as your old card.

Finally, I would open up the PC case and watch what's going on for a few minutes with the fans. If you're not sure which one is starting/stopping, getting a visual on it will help.

Hope these tips help.