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by azalemeth 1302 days ago
Honestly this isn't more than I cared to know about PC fans. I've worked extensively with industrial appliances and fans are bloody important and underlooked: fan failure is often the step that precedes component failure. The one part of the spec I wasn't aware of was just how insanely high the maximum current draw is; I'm glad that we've made more efficient, longer-lasting, effectively silent air-movers that can fit easily within that power budget.
2 comments

Adding fans to consumer devices that don't have them but should, such as a cable modem, certainly improves its reliability in my experience!
The problem with that is when the fan would block the natural venting if it stops working. These devices are engineered to have the heat move the air through and out of the device, and though a fan will usually do a better job of that, it will ultimately fail. When it does, if the fan body is in the way then the intended convection is blocked and the entire unit shuts down or is damaged.
Cable modems are often placed in poorly ventilated spaces that overheat. So you can get the best of both worlds by including generally unneeded fans which enable the device to function in sub optimal conditions, but can also extend lifespan in better ventilated spaces.

The alternative of passive cooling in such spaces is unreasonably expense because only a subset of devices are subjected to such conditions.

I have thought about adding a bathroom style vent fan to the closet that houses the network gear for the house. Exhaust near the top and have a cool air intake near the floor.
AC Infinity make fans specifically for this purpose:

https://acinfinity.com/closet-room-fan-systems/

Bathroom fans work too if you’re able to vent through the ceiling. I can recommend the Panasonic whisper fans (available under a variety of models with “whisper” in the name). I’m using one to exhaust the warm air from my home theater emitted by the projector. I think it’s this one:

https://na.panasonic.com/us/home-and-building-solutions/vent...

Slow big fans on my home receiver kept it going much longer than it probably would have lasted passively cooled.
Can you recommend a fan setup for that?
AC Infinity usb fan on amazon. Silent, but moves enough air, and you can bump up the speed.
yeah, if you look at the equations at the bottom, power goes up with the third power in relation to rpm. whippin' and drivin' that much air takes some oomph. connect that fan to any normal motherboard, and you're going to burn out your fan header pretty much immediately (especially since inrush current is probably even higher than the steady state).
For those interested, the equations are also known as fan or pump affinity laws:

https://www.engineeringtoolbox.com/fan-affinity-laws-d_196.h...