Sunon 40x40x20mm 3 pin fan #KDE1204PKVX

I bought these to help cool my delta printers NEMA17 steppers. I attached them to some uxcell Aluminium 40 x 40 x 11mm Square Heatsinks (which they sell here in a 10 pack). They have been working great and my steppers now run cool. I would not characterize these as quiet fans, but they are also not loud for the air they move. They have been running for hours on end and so far no strange noises, and my experience with this brand has been good in the past.

Sunon is an industrial grade fan supplier (vs all the PC-grade Chinese junk fans out there). Other industrial grade fans are Delta, NMB, Panasonic, Orion, and Papst, Sunon Maglev fans tend to be very long lived. A good bearing design and lubrication is especially important in 40mm fans as they run at much higher RPM than larger fans. The higher speeds create more wear. Maglev bearings are also quieter than ball bearings. But, running at full speed, this fan isn't exactly quiet. It will, however, start and run on 5 volts (instead of the intended 12 volts) and is nicely quiet but, obviously, doesn't move nearly as much air on 5 volts. If you have a motherboard that will control a 3 pin (vs 4 pin PWM) fan, or have another way to slow it down, this is a good choice. Beware that some 4 pin motherboards will only speed control a 4 pin PWM fan.40mm fans are either noisy or move very little air. You can't have both. At least this is 20mm thick which helps it move air than 15mm or 10mm thick fans for a given speed and noise level.

I ordered one of these from (Seller A) and received the proper model #KDE1204PKVX with maglev shown in the picture. it's a good fan, blows a lot of air, though it's a little on the noisy side, it was what I expected and a good still running fan so I ordered a second one, this time it ended up coming from (Seller B) when it arrived it was the #KDE1204PKB2, not the #KDE1204PKVX shown in the picture. the #KDE1204PKB2 is a lower quality fan of the same size from the same maker, it pushes less air,. Is not MagLev, and is very, very noisy. In addition its almost dead after about a week of running,. If you order this fan make sure it says #KDE1204PKVX when you get it, If it does you should be happy, if it does not send it back ASAP it's not the fan in picture or the description and should not have been substituted like that.

Like most, I bought this to replace failing fans. I'm hoping the mag-lev will outlast the original fan bearings, but I haven't had it long enough to speak to the longevity of the product.Unlike another reviewer, I was happy to find that I did not receive a substitution.It's slightly loud, but that's not a complaint. The noise is quite reasonable given the high CFM rating for the size.

Tried to put these into a network switch. (An HP ProCurve 2848.) At first, I thought this would be a straightforward swap. Old, rattling fans out; new quiet fans in. What I found was that these fans simply wouldn't spin. Compared to the stock fans (which *did* spin, but were noisy) the connectors were identical, the layout of the pins was identical. Power consumption (according to the stickers on each) was identical. Tried them with multiple connectors on the board. Ordered three of these, none of the three worked.

Jumping from page to page in my browser looking for a specific fan and the best price. I got it here on Amazon because the prime shipping and all that.I had the fan picked out and found the best price/shipping combo. It arrived and it's the wrong fan.The fan I was ordering is the one pictured on the sellers listing, MB40201VX. What I got was the KDE1204PKVX.It is half my fault for not noticing the item listed in the description is not the same as the one pictured. However it's just bad that they didn't display the correct item or enough information in the description to know the difference (the CFM is different 6.8CFM vs 10.2CFM)In addition to that the other major let down is the fact that it does not come with screws for mounting, so keep that in mind as well. This is the first time I bought fans of any kind that did not include screws.

I use this fan to keep my 3D printer's extruder cold-end cool, and it's a massive upgrade over the original fan. I run it at 5v, which leaves it completely silent but still very effective. At 12v it's a little bit loud, but really moves a ton of air.

I'm using these in a Brocade ICX 6450 48p as the stock fans were extremely loud. These are quieter but not silent. This switch is in my garage so it doesn't need to be silent, but I couldn't consider having it in the same room with me, even with these quieter fans.If you are going to use these in a Brocade switch, make sure you follow the tutorial on youtube which describes the wiring differences as you need to swap two of the power pins.