AC Infinity MULTIFAN S4, Quiet 140mm USB Fan

Im writing this review during a very HOT unusual few June weeks in Minnesota, its been over 90 for almost 2 weeks now, I have a full size 42U server rack for my home lab, it has a big hole on top that nobody's exhaust fans fit, 21 x 5.5, but the 140mm measurements of this fan is just big enough that I can sit about 4 of them on top of the racks hole. I work in Tech Recycling, so I see what happens to most tech equipment when its removed from service, its rare to see AC Infinity products, I rescued a old AC Infinity Controller they don't appear to sell anymore, but its similar to the one they sell now, and rescued a 2U Rackmount 4 fan with controller unit, I was amazed how quiet the rack mount fan unit was even after many years of use, the LCD controller is a bit hard to read, but other then that it works fine. So I needed some USB fans to plug into the other controller I rescued, I was concerned there was only 2 USB ports, which is the same as new model they currently sell, but when these fans arrived, I saw a lovely daisy chain USB connector, apparently you can have up to 4 of these on 1 of the USB controller ports so those 2 ports give you maybe 8 fans , I don't need that much, but its a nice feature, I plugged these in to the old controller set it on AUTO and away they go. The controller appears to have Low/Med/High setting but these fans also have a 4 way switch on the cord which seems to be 1 notch higher then whats available on the controller, I have them maxed, very light hum, not much more then my laptop fans on a hot day. Compared to others, I have rescued hardwired plug and run fans with no thermostat, that sound like a bunch of servers running, so these are by far the quietest ive heard (almost can't tell they are running), Now that I know they daisy chain, I bought 2 more, with 4 of these at about $15 each vs $300-400 exhaust fans that are usually 120mm, they sell for most racks this is a great deal and larger. Perfect product, not sure how strong they are? they are not as FAT/DEEP as some Ive seen at work, its very hot, my rack runs about 3-4 degrees hotter then the room its in, so even with the fans they are having a hard time cooling it down, but air circulation is always good. its hard to get cool when the room itself is hot upper 80s, and rack is maintaining lower 90s. Only thing I would add to this product, RGB colors would be nice for those of us that like adding colors to our loved computers, but probably wastes electricity and reduces power so maybe its better they don't have color lights. (only if it don't sacrifice cooling power) CLIPS, since Im buying 4 of these to fill that big 5.5 x21 inch hole in my rack that normally a bunch of wires would go through, but in my home lab all wires go down, Im using that hole as a exhaust for the heat to exit up to the ceiling, these cool rubber feet are nice, but it would be nice to clip these together with some kind of clip so instead of 4 loose fans its 1 big fan. The feet are good, but since I have 3 cats that can jump on top of the rack it would be nice to link these fans together with some kind of bracket or clip just in case, not too worried about it, but it would be a nice modular feature. Lucky for me its only hot in Minnesota 3 months a year, so most the year these fans won't have to work hard, but they are running 24/7 now in a near 90 degree room. These would be great for quiet rooms, chances are your normal household fan is louder. Love the product, both the old ones I rescued that were not quite ready to be recycled yet, and these new fans.

Bought these during the summer when my internet started cutting out. Turned out my router and modem were overheating. Added these AC Infinity USB fans and the problem was immediately fixed. They’re quiet, move plenty of air, and I really like that they can be daisy-chained so multiple fans can run off one USB port (I daisy chained the 120 and 140 together and plugged them directly into my router). Setup was simple and clean. They’ve been running continuously for months with no issues. Solid, reliable, and absolutely worth it.

This is a great fan for my PS4 and I can put my laptop on it to keep it cool, I like the fact that you can connect up to 5 fans and very quiet.

Very quiet! Works great. Using it to cool down my NAS.

This product does a good job of cooling my PS5. I place it behind the PS5 and turn it on. There are several speeds. The unit is quiet. I start the fan when I turn-on the PS5 so that it won't overheat inside the entertainment console. The price is very competitive, and you can added another fan if necessary. You have the ability to couple additional fans. I strongly recommend this product...

Holy cow, these are ridiculously good fans. The 140mm size is amazing because it moves more air across a broader current at a whisper-quiet volume. AC Infinity gear is always top notch, but I truly love using these fans in my plant cases. At low speed, it is literally silent.

What a quiet fan. It works very well and is perfect for what I needed.

Nice 5" fan. Not a wind machine. More of a gentle breeze. I use it to cool my Tablo. I added a small piece of foam AC filter to keep out dust.

静音タイプの冷却ファンで、スライドスイッチによる弱中強3段階の運転モードが選択でき、ファン同士の連動運転も可能となっている 前々からPCの冷却手段に導入しており、優秀なファンというのは既に実証済み。今回は、自分でレストアしたDENONのプリアンプの延命処置として予備機1台を使用したが、電源トランスの排熱量が予想を超え、1台では明らかに能力不足だった為直ぐに2台目を購入。 ファン側での連動運転はせず、プリアンプ側の電源で同時運転させているが、2台動かしていても中運転までなら全く気にならないし、電源トランスの排熱も良好。シンプルながら信頼性の高い冷却ファンだと改めて実感。 ゲームハード等の冷却にも大変オススメ！

I use them to cool my Desk NAS, they are silent, have good airflow and do not vibrate - perfect for my application.

Excelente producto, excelente acabado y presentación, funciona perfecto, enciende y apaga junto con el receiver conectado al USB, o si compras el cargador lo conectas al regulador o al enchufe de pared. es lo más recomendable para evitar daños al puerto USB del amplificador, es silencioso, imperceptible incluso a volumen bajo y el receiver trabaja mucho muy fresco en la velocidad más baja del ventilador, que impresionante, mega recomendado! He comprado 5, uno para cada amplificador.

Veilig met de roosters en stil. Goed te plaatsen met de rubberen steuntjes en/of met een schroef/boutje door deze aansluitingen Voldoende luchtverplaatsing voor mijn doeleinden. Maar je kunt er makkelijk meerdere aan elkaar koppelt één voeding

Quiest aesthetic fan. Small, light, and works well. 4 mode.. off, low, medium and high. I have it mostly on high as electronics is inside an enclosed area. Unfortunately there is no auto on/off switch.. would be perfect if it automatically turns on everything my electronics go on, but I am not sure if there's such a product currently on thr market. This is a great fan, may get more.