Laptop fan revving

[Aniallation]

So my mom recently got a laptop from her friend for a decent deal ($55) just for around the house use, it's a Dell Inspiron 15R, with i5-2430M, 4GB of RAM and Windows 7 Home Premium, seems to be original as it has all the bloatware on it.

 

So far it seems to be excellent hardware wise except for one thing which is the fan. It's always on which isn't a big deal, but it's loud and is constantly revving. It won't stay at a constant speed, and feels like it's getting power applied to it for a second, then off so it slows down for a second, and then repeat. It's not consistent either, the gaps between revs fluctuate, it's not a constant gap. Like this, but with fan noise rather then exhaust. https://youtu.be/r8hG3bDI7Dw?t=8s

 

Anyone know what's going on or how to stop it from doing this? The noise of it gets really irritating.

 

-It does it in the BIOS as well, not just in Windows

-Took it apart and cleaned the fan and heatsink, unplugged fan and plugged it back in again, still the same

-SpeedFan doesn't work, even with Dell control enabled

[bob345]

So my mom recently got a laptop from her friend for a decent deal ($55) just for around the house use, it's a Dell Inspiron 15R, with i5-2430M, 4GB of RAM and Windows 7 Home Premium, seems to be original as it has all the bloatware on it.

 

So far it seems to be excellent hardware wise except for one thing which is the fan. It's always on which isn't a big deal, but it's loud and is constantly revving. It won't stay at a constant speed, and feels like it's getting power applied to it for a second, then off so it slows down for a second, and then repeat. It's not consistent either, the gaps between revs fluctuate, it's not a constant gap. Like this, but with fan noise rather then exhaust. https://youtu.be/r8hG3bDI7Dw?t=8s

 

Anyone know what's going on or how to stop it from doing this? The noise of it gets really irritating.

 

-It does it in the BIOS as well, not just in Windows

-Took it apart and cleaned the fan and heatsink, unplugged fan and plugged it back in again, still the same

-SpeedFan doesn't work, even with Dell control enabled

its likely the cpu is overheating. Check the temps with a monitor like hwmonitor

[TheSLSAMG]

So my mom recently got a laptop from her friend for a decent deal ($55) just for around the house use, it's a Dell Inspiron 15R, with i5-2430M, 4GB of RAM and Windows 7 Home Premium, seems to be original as it has all the bloatware on it.

 

So far it seems to be excellent hardware wise except for one thing which is the fan. It's always on which isn't a big deal, but it's loud and is constantly revving. It won't stay at a constant speed, and feels like it's getting power applied to it for a second, then off so it slows down for a second, and then repeat. It's not consistent either, the gaps between revs fluctuate, it's not a constant gap. Like this, but with fan noise rather then exhaust. https://youtu.be/r8hG3bDI7Dw?t=8s

 

Anyone know what's going on or how to stop it from doing this? The noise of it gets really irritating.

 

-It does it in the BIOS as well, not just in Windows

-Took it apart and cleaned the fan and heatsink, unplugged fan and plugged it back in again, still the same

-SpeedFan doesn't work, even with Dell control enabled

If temps look fine, it could be an issue with some on-board circuitry or maybe the fan itself.

[Aniallation]

its likely the cpu is overheating. Check the temps with a monitor like hwmonitor

 

If temps look fine, it could be an issue with some on-board circuitry or maybe the fan itself.

 

It's at around 45c browsing the internet, so definitely not a temperature issue.

[bob345]

It's at around 45c browsing the internet, so definitely not a temperature issue.

 

hmm, thats annoying. May just be a very poorly implemented fan curve. Not sure if there is anything that can be done about that if the controller is separate from the rest of the system

[Swisscheesy]

So my mom recently got a laptop from her friend for a decent deal ($55) just for around the house use, it's a Dell Inspiron 15R, with i5-2430M, 4GB of RAM and Windows 7 Home Premium, seems to be original as it has all the bloatware on it.

 

So far it seems to be excellent hardware wise except for one thing which is the fan. It's always on which isn't a big deal, but it's loud and is constantly revving. It won't stay at a constant speed, and feels like it's getting power applied to it for a second, then off so it slows down for a second, and then repeat. It's not consistent either, the gaps between revs fluctuate, it's not a constant gap. Like this, but with fan noise rather then exhaust. https://youtu.be/r8hG3bDI7Dw?t=8s

 

Anyone know what's going on or how to stop it from doing this? The noise of it gets really irritating.

 

-It does it in the BIOS as well, not just in Windows

-Took it apart and cleaned the fan and heatsink, unplugged fan and plugged it back in again, still the same

-SpeedFan doesn't work, even with Dell control enabled

 

Oh no I had exactly the same problem on exactly the same laptop except that mine shuts off after one "rev cycle" and I still haven't fixed it. I even replaced the CPU thinking the temp sensor was bad and nothing changed. In my case I think that something in the motherboard circuitry is bad.

[mzarrugh]

Check if there is a BIOS update available.