Take the 2-minute tour ×
Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

On my new PC, the component making the most noise is the rear exhaust fan on my case (it is the only exhaust fan in my PC). I tried to disconnect it and watched temperatures in SpeedFan and CPU was usually at about 35C, peaking to about 50C when the system was under load - this doesn't look too bad.

So I'm considering that I'll leave the exhaust fan disconnected permanently after which the computer is very quiet - the only noise-making components are Arctic Cooling Freezer 7 Pro Rev.2 (CPU fan) and PSU fan (Enermax Pro 82+), both being quiet enough as far as I can tell. (My GPU has a passive cooler.) Also, those 2 components are moving parts so will provide some air flow in the case and, even better, PSU fan sucks the air out of the case so it kind of is an exhaust fan in itself.

Does anyone run with the exhaust fan disconnected? You don't have to tell me that it's always better to have more air flow than less, I know that, but the noise is also a consideration for me and temperatures around 40C should be fine shouldn't they?

(I might also consider getting a quieter case fan but I'm specifically interested in your opinion on the no exhaust fan scenario.)

share|improve this question
add comment

5 Answers

up vote 7 down vote accepted

It is worth checking if your BIOS has options to shut down the PC based on the temperature of the CPU. This means if you do decide to run without the exhaust fan then your PC would shut itself down if things were getting too hot preventing damage to the components.

And in reply to your bracketed comment, I would say it's really worth looking into replacing the case fan. The difference in noise between stock components and third-party replacements costing only a few dollars can be huge. Another option would be a fan speed controller so you can lower the speed of the case fan so that it is much quieter but still provides some air flow.

share|improve this answer
add comment

This is a good article on airflow in a computer case.

share|improve this answer
Very surprising results. Not too worried about missing my side fan anymore. However, many desks put a PC case in an enclosure with very poor circulation often only allowing the best air flow from the rear. I should install a sleek looking vent in the front of the cabinet door. –  IAbstract Mar 15 '10 at 17:32
add comment

From the product-level perspective, if you have a new system, the vendor probably will not provide hardware (repair) support if you have disconnected it.

If you assembled the system yourself, those considerations do not apply.

share|improve this answer
I've assembled this computer myself. –  Borek Mar 15 '10 at 10:01
add comment

The CPU is only one component of several in your case that need to stay cool. What about HD, GPU, Motherboard (North & South Bridge)? I would monitor the temps for those as well. Considering the article on airflow listed in the other post, I would just get a good, quiet rear fan. Heat kills.

share|improve this answer
add comment

If the PSU fan already seems to provide enough air-flow, the additional case fan can be left off. Even more so as though your graphics card has passive cooling.

It looks like the additional fan is overkill in your case.

If you find that you still need it, try to find vibration-decoupling fan mounts. They help a lot.

share|improve this answer
I thought that GPU with passive cooling would actually increase demand for a good air flow. –  Borek Mar 15 '10 at 10:16
True; I think, however, that the PSU fan produces enough air-flow (if the case is closed). Yes, my answer was badly written. I'll fix it. –  brandstaetter Mar 16 '10 at 11:13
add comment

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.