NoctuaNF-A12x25 PWM, Premium Quiet Fan, 4-Pin (120mm, Brown)

This is actually too good for me. I bought two of these to put on the rear and bottom of my Raijintek Styx case. The build has a Tuf Gaming B660m-plus WiFi board and a 12700k CPU and no GPU card. I figured a CPU as hot as this is supposed to be would make keeping the case cool difficult even with my crazy Arctic Liquid Freezer II 240 AIO I also bought and left the stock fans on.Right out of the box these fans are hefty. There's some meanness just in holding onto it. Much heavier than I'm used to, no doubt about it. They exhibit a lot of weight just on the blades themselves. Give it a flick and notice how long it takes to stop. It's not quite a fidget spinner but closer than anything else I've tried that calls itself a computer fan.The cable sleeves are a nice touch. corner Bumpers are nifty. Not too hard to pop them off and install the included gasket thing that you can use to block all air from escaping around the sides (between the corners) (recommended for use on high pressure applications like Radiators). The included and pre-installed bumpers cause a gap of about 1mm all along the sides that some air could escape through otherwise. Another solution is just to remove the bumpers from the corners on the side that you will have against what ever it is this is going on. In theory that'll result in more noise but a tight seal is assured.The anti-vibration mounts are little rubber tubes that you can pull through the screw holes. the longer end goes through the fan all 25mm and sticks out the other hole. The shorter end you pull through the screw hole on your case or what ever. The ends of these are tapered, you pull hard on it until the wide part pops through. I wouldn't use that to mount it on a radiator. I didn't use them on the case either, but some might prefer it. I think this is ideal for a temporary install though. You can pop them back out, hopefully not breaking the tube off in the process and easily reuse elsewhere. These do stick out a ways. If you're gonna use it somewhere there's not room for the little rubber tube to stick out you can cut it off once you have it installed, but doing so will make a future installation using the same mounts more difficult as you no longer have anything to pull on.My setup lets the CPU package have 144 watts at all threads max load, 4.7ghz p, 3.6ghz e. The darn AIO which I have on top pushing air out is so mean it's keeping the whole case cool all by itself. Meanwhile, I can stop the fans on the AIO and these Noctuas are mean enough pushing air into the bottom and back of the case to passively cool the AIO's radiator, lol.My CPU idles around 72f, temp sensors on the Motherboard between 72 and 93f while doing light load tasks like web browsing. My case is cold to the touch.I put one of these on the other side of the radiator from the stock fan, set it to half speed then gave the stock fan a flick with my finger, it wasn't being powered. It got enough force from the Noctua all the way through the thick radiator to keep spinning, with the Noctua at half speed!This is one mean fan! I did find that if I put my ear right up against the back of the case with the rear Noctua spinning, I can hear the blades going by like you can hear if you go behind a box fan and hear if you talk through it. It's a rather obvious and loud pop every time one of those many blades go by. But at anything more than say 5 inches you can't hear that part of the sound at all.I have no trouble hearing these in the Styx case if I turn them above 40 percent but they really move an incredible amount of air even at low speeds, so if you need quiet, these can do it, just use the included LNA adapter or set the curve in the bios or using a third party program like Asus AI Suite III or Fan Ctrl. These are probably a good investment even if you will limit the speed because their pressure and airflow is so great.For my purpose, the cheaper Redux1700 option would have been fine. I put those on another build I did a while back and they work well there and are not noisy.

Update 04-14-2019: The circumstances of my build have changed. I have converted out to an open loop with (2) 480mm x 60mm radiators and in pull only configuration I use the NF-A12x25 PWM fans to handle to air movement. I have two more NF-a12x25 fans as separate exhaust and @ 900rpm on my loop, my 2700x and 2080 Ti are silently cooled. These fans are truly amazing in noise for flow with these thick 60mm radiators, particularly in the 700rpm-1,300rpm range. I can barely hear all 10 of them from 3 feet away @1,200rpm but at 900 they are truly inaudbile and keep the 2080Ti @ 2,115MHz and 43°C in any load indefinitely. For applications where the lowest possible noise for air moved through radiators is required or desired, look no further.I couldn't stand the AIO pump noise from the NZXT Kraken x62 on my Ryzen 2700x build. After listening to a couple of other systems with the EVGA CLC280, Corsair H115, and H150 I determined that my ears are just tuned to pick up water pump noise. So the next step was the best air cooling solution I could find: The Noctua NH-D15 SE-AM4. With my case the stock NF-a15 fans for that heatsink assembly wouldn't clear both the ram and the case side panel. Thanks to some reviews for this fan along with Noctua saying it was a compatible match, I decided to try these fans for the heatsink in order to keep the twin fan capability. I also opted to replace my (7) NF-A14 PWM case fans with (6) NF-A12X25 fans. I was intrigued by the development cycle and the promise of excellent low mid-range to high mid-range rpm pressure and flow rate.These fans deliver in a way the fringes of my hopes dared to imagine possible but didn't actually expect to exist. With the NH-D15 SE-AM4 I obtain the same boost clocks with only a 2c penalty in Prime 95 small FFT or Folding@Home CPU work units vs. the NZXT Kraken x62 with push, pull or push/pull NF-A14 fans. Where the kraken required the fans spun up enough to be audible from 3 feet away and on par (by ear) with the AIO pump noise to achieve the reference level of cooling the NF-A12x25s lose 2c at 950rpm: they are not audible without my ear in direct contact with the case. Best of all, I am running the AMD Ryzen 2700x at 4.1ghz all core under Prime 95 or F@h CPU and hitting 66c worst case scenario and the computer is completely silent at the seating position 3 feet away. This is well within temperature guidelines from AMD, at a significant boost over advertised all core boost clocks that is sustainable indefinitely and while having a total CPU and SOC combined 130 watts of power used. The pure silence and the temps at full load wouldn't be possible any other way. I tried. The Sterrox polymer based NF-A12x25 is a triumph in design and execution whose value is priceless and performance is peerless.