I bought this fan to put a permanent end to my heat creep issues with my 3D printer. I actually have to run at it less than half speed, or else it does its job too well and the extruder heater goes under temp. This thing is loud enough that it could probably cause hearing damage at max power given enough time, making it unsuitable for basically any application other than servers if you plan to run it at full speed.

I am using for a diy 12715 peltier cooling plate. As you know the 12715 module can pull 12v and 10-15 amps. It's a monster of a peltier. With a single albeit huge aluminum heat sink, plenty of thermal grease and just this singular fan mounted to a PWM controller, I was able to consistently get the semiconductor stable at around 3° f with only this tiny fan cooling the hot side. That was stable temperature too, not peak. Big difference. I could run that 3° f all day long without the heat overpowering the fan. This was achieved with the fan at full power and the semiconductor pulling around 10 volts and 6 amps. Nowhere near its peak, but impressive as all hell. It's the positive pressure design of the fan with almost a built-in duct because it's so thick as well as the RPMs which I've heard is around 18,000 at full tilt. It's pretty much a cold air hair dryer at full throttle it can blow papers off my desk from across my room which is quite large and actually has some kickback, that's how powerful this fan is. With the setup I mentioned above I was able to achieve about a quarter inch thick layer of ice on the cold side heat sink on the semiconductor within 35 minutes of 6 amps of continuous draw from my 300 watt adjustable power supply. From what this singular fan proved to me, I figure if I order three more and a much bigger heat sink to accommodate, I could run that semiconductor close to full capacity with no cooling issues whatsoever. I thought for sure I'd have to go water cooling for a 12715 but these fans have proved otherwise. They are extremely loud when at full throttle but for my application, which is intermittent fast cooling of electronics on a cold aluminum plate, this is just fine as it runs for very short periods so the turbine like sound of this fan doesn't bother me too much. It is very much a turbine sound though, it's almost ear piercing if left on for a long time, thank God for my Galaxy buds 2 pro with active noise cancellation for the longer sessions because this sucker really screams but it puts out the CFMs to back it up so I don't mind the noise.I've been using it a few times a week for around 3 months now with some sessions having the fan run full throttle for close to 2 hours at a time with absolutely no issues whatsoever, the most I've ever experienced is after about 2 hours the fan will be slightly warm to the touch but that could be from the peltier as well. All in all it was a great buy and it blows just as much air as it did on day one as it does now. It's become old faithful for me and moves easily 5 times the air as my 120 mm 12 volt 0.25 amp fan. Granted the 120 mm is nowhere near as thick so there's no ducting whatsoever and I don't believe it's meant for positive pressure like this is but still these little things seem to be the way to go if you want to successfully cool off a ridiculously angry power-hungry peltier module. Just make sure you get a really high-end heat sink. The heat sink is the most crucial part of any semiconductor setup. Mine is milled from a solid block of aluminum with copper vapor chambers at each corner running down to the hot side ventilation blocks, there are four copper vapor chambers running to two cooling blocks I plan to have two of these fans on each cooling block and I have no doubts I'll be able to run my chip at it's a rated maximum without any overheating issues since I can run it more than half of its capacity with just this single 40x40 fan

this fan moves a ton of air at high static pressure.. it is noisy if you run it on full speed 2 wire mode (black / red). sounds a little like a mini vacuum. with the high RPM it means the fan can generate good static pressure.. works great for 1u servers where you pack in a lot of SSD drives and need extra air. the connector on the end is smaller than what most fan connectors on motherboards support, you will either need an adapter or to make your own connection. these do fit supermicro 1u server cases but connector needs adapted.

These fans are meant for 1U rack servers and network devices. This particular model is specified to reach 18,000 RPM, which is around the maximum for this fan size, and equipped with ball bearings for durability. It cannot therefore be expected to be as silent as models without ball bearings, but should last years longer than the latter.My application is as replacement of the original fans of a Cisco ASA firewall (known to ramp up the fan speed to maximum every few minutes, which results in a sudden increase of the fan noise), and in this application they make the noise slightly more bearable than the original shrill whistle. I previously tried using Noctuas in the same device, which are far more silent, but their RPM speed was not sufficient to keep up with the necessary airflow and caused continuous alarms.

Good quality.. and fast. But very loud motor