Fan won't start up

By Ano2
Feb 13, 2007
  1. Hi all, tech noob here.

    My problem is with my friend's computer, basically when it starts up the fan will start up for about 10 seconds then stop completely, causing the computer to overheat and shutdown.

    So I really need either a way to automatically start the fan, or a way to solve the problem.

    Cheers, Ano2.
  2. SNGX1275

    SNGX1275 TS Forces Special Posts: 10,689   +395

    Check the BIOS settings for anything to do with a fan. I have to be general here because you failed to provide any information about the system other than its a fan.

    How long will it run before shutting down?

    The fan runs on 12V, so if all else fails you can just connect it into one of the lines comming off your powersupply so you will feed it a continual supply of 12V. This can also be ran at 3.3V and 5V, and if you are sneaky you can get some interesting voltages such as 17 out of it.
  3. Ano2

    Ano2 TS Rookie Topic Starter

    Hi, sorry for the lack of specifics, its a packard bell PC running with an athlon 3000 I think, unsure as to the motherboard make.

    The computer runs for a variable amount of time, and usually shuts down once the cpu tempature exceeds 90 degrees celcius. I think it may be a problem with the heat sensor, but I don't know what it is, or how to check it.

    I tried to start the fan in the bios, howeve rit only allowed me to check the fan speed and create a warning signal.

    Any help would be greatly appreciated.
  4. SNGX1275

    SNGX1275 TS Forces Special Posts: 10,689   +395

    Take the side of the case off and run a box fan on it so you can get into Windows and download a program called Speedfan. See if you can control the speeds through that.
  5. Ano2

    Ano2 TS Rookie Topic Starter

    I d/l speedfan, howeve rit won't let me control fan speed (or start it up anyhow).

    I think the problem may be to do with the heat sensor, anyone got any ideas what I should do?
  6. Tmagic650

    Tmagic650 TS Ambassador Posts: 17,233   +234


    see if there are any fan control options in the systems bios. If there are, turn off all fan controls. If not, replace the CPU fan, and remember to clean off the old thermal compound and apply a SMALL amount of new compound to the heatsink
  7. zipperman

    zipperman TS Rookie Posts: 1,179   +7

    Get a new fan and heatsink as soon as possible and save the cpu.
    But installing really needs an experienced installer.
    The new fan should include installation directions if you want to try.
    My son did mine and had to remove the motherboard.
    It's very important to do it right.
  8. Ano2

    Ano2 TS Rookie Topic Starter

    Cheers guys, I will try to install a new fan, thoguh it does look a bit complicated :S So if I install new one, it should hopefully start up on its own?
  9. KingCody

    KingCody TS Evangelist Posts: 992   +8


    if you don't feel comfortable changing the fan then you should try SNGX's earlier suggestion and power the fan directly from the power supply. you can buy a simple 3-pin > to > 4 pin molex adapter like this:

    you may already have one lying around somewhere, but if not they only cost a buck or two. if the fan still has the problem even when being fed a constant +12V then the fan itself is bad and will need to be replaced.

    cheers :wave:
Topic Status:
Not open for further replies.

Similar Topics

Add New Comment

You need to be a member to leave a comment. Join thousands of tech enthusiasts and participate.
TechSpot Account You may also...