Want to completely remove system fan from Dell Optiplex

JethroC

Hi all,

I want to completely remove the system fan from a Dell Optiplex 170L but as with all Dells, when the fan is removed the computer will stop on boot up with a message saying that the fan has been removed or whatever. Does anyone know if there's a way to either trick the motherboard into thinking the fan is connected and working or to get rid of the message?

I'm using the Optiplex as a NAS box and from time to time the system fan will go crazy for some strange reason even when the computer has been idle for a few days. I need it to be almost silent as it is located in my sitting room where the family would spend most of our time. I can possibly leave the side of the computer off if I find away around this fan issue.

Any help is appreciated.

Cheers! :P

Steoob

Well the fans obviously there for a reason. It will overheat without it... Dont really know what else to say to be honest without giving advise on how to potentially set your house on fire.

snappieT

PC will cut out at 70 degrees anyway, so no need to worry about fire risk, so long as there's some other fan spinning.

OP, I don't know of any way to solve your problem. Would you not put a resistor in line that would set a lower peak speed for the fan instead?

Alanstrainor

You'll just end up blowing the motherboard. It happens quite a lot on our machines in work. The capacitors on the mobo just burst with the heat. I'd be inclined to leave it there tbh.

leninbenjamin

Can those fans be replaced? You might try putting in a Scythe or Noctua fan, they'll be quieter and blow more air meaning it probably wont go as crazy as often.

JethroC

I can't see this machine overheating tbh...there's only one fan in it which is the system fan. If I can remove this and leave the side of the computer off I think it will be more than enough to cover any possible overheating issue. There's a massive heatsink on the CPU so that should be enough to take the heat away from the CPU itself. The temps I've recorded on the HDs when the NAS is in use for a long period are about +/- 35 degrees which is perfectly fine. I think with the side cover off that could even drop a little more. Pity there's no BIOS setting for the fan considering the computer should run perfectly fine without it...

snappieT

No way, even I'm going to stop here. Unless you have a very low power CPU or a huge passive heatsink, you need a fan. It's not like it's in a shed where there's a cool draft. It's in a living room with heating and people and other equipment emitting heat.

You're asking for trouble.

lucernarian

Cooling by conduction (e.g. heatsinks) only work when there's a temperature gradient to allow heat to move from the CPU etc. to the outside environment.

No fan means you end up with a hot heatsink, and only a little bit of convection, depending on the case and ventilation, to cool it. Air has a poor heat capacity so the air right beside the heatsink will reach the same temperature of the heatsink quickly, hindering further flow of heat from the CPU.

In other words, it's a bad idea!

JethroC

Hmmm...might be a better idea to find a quieter fan then. I thought leaving the side panel of the computer off would be sufficient cooling for the CPU heatsink as it's a monster of a thing. Ahh well! Thanks for all your help...:P