ARCTIC F8 PWM PST- 80 mm PWM PST Case Fan with PWM Sharing Technology (PST), Very Quiet Motor, Computer, Fan Speed: 300-2000 RPM

I bought this one to replace the very old and failing fan built inside the ATX power supply of my home brew DVR. (A pc with tuner cards)The original was a cheap made in china power supply made in 2003. Last year the old fan locked up and the house smelled like a fire was going on. Took it apart cleaned up the fan and re oiled it. That worked until last summer when it started making horrible noises again. I ignored that and just now installed the new fan. I had to replace 9 failed capacitors on the motherboard anyway, since it totally died the other day so changed out the fan as well.I had read that a PWM fan sometimes will not work by just supplying 12 volts and ground without the use of the feedback line for the PWM drive. I tried this first with a 9v battery to see if this one would work that way.At first it did act like it required the PWM input. (would start, run a few seconds, then stop) for whatever reason after doing that a few times, it ran reliably and constantly at full speed on the battery only.I tested the PWM input and it is already at a logic one voltage-wise so has a pullup resistor inside.Put the thing into the power supply, finished the job on the rest of the computer, and its working flawlessly.It is very critical that the fan in the PS of that computer ALWAYS runs for this application. The DVR pc is set to turn itself on and off as programmed to record over the air TV. I may or may not be at home when it does that, I may or may not be sleeping at the times that it decides to switch on or off.Reliability is critical. I dont want to come home to a burned down house some day.This fan is not my first purchase of the same type from the same company.I changed 2 of the fans in my normal pc with this same type and brand (2 bearing PWM) some 3 or 4 years ago to pull air in and pressurize the case through homemade filters. Different sizes of fans. Those two using the PWM on the motherboard.They still operate near silently. Speed is regulated by the system BIOS according to temp sensors and power demand.They still havent degraded in any way.Extremely well made and reliable fans at a reasonable price.

Very quiet you cannot hear it running, great for my amplifier, moves enough air to help keeping the Amp cool.

PRO:-relatively inexpensive for fans (albeit a bit pricey for 80mm fans)-PWM support, so you can control the speed easily, or automatically, depending on your application.-pretty quiet, I wouldn't call them silent but they don't bother me. I installed these in a server, where they are still more quiet than the other fans.-dual ball-bearing design for long life and reduced friction. Most fans use "sleeve bearings" which are basically two cylinders (one inside the other) with a layer of oil between them. Fans with sleeve bearings generally wear out before ball bearings.-installation screws are included, so no need to buy any.CON (really none, these are more explanations, and nitpicks.):-ball bearings make these fans more expensive than if they used another kind of bearing. Still, $9 isn't bad.-two tone color might not be your ideal design (but since fans like these generally go inside an enclosure, you shouldn't be looking at them very often. two more colors on the sticker brings these to 4 colors, which is pretty aesthetically loud.-sticker on fan blade hub, could eventually come off and get stuck in blades (I've seen this happen but not on this model of fan)

Needed something silent for my HTPC build and these seemed to do just fine. They were relatively cheap and I like the PWM function where you can connect it directly to the CPU fan. It exhausts hot air out of my HTPC and keep things cool. Notice they say it is low noise so they are not absolutely silent but they aren't noisy either unless your CPU is working overtime (overclocked). You will hear them if you are few feet away but further back you will not notice the sound. All of this depends on your setup of course and type of CPU, and how ventilated your case is.