Never was that enthralled with Noctua fans, but the 40mm noiseblockers I have seem quite good.

I replaced all the 40mm fans in my Cisco CCNP lab kit with these and they have been silent, even back when the “cab” was an Ikea LACK next to the head end of my bed!

You always get some noise from the more compressed air at leading edge of fan blade or underside trailing edge hitting static objects in immediate vicinity. This is made worse by number of edges. So right on top of a heatsink is worst case scenario, as is right next to a grille.

Fortunately however, this is MUCH reduced by increasing spacing a mere millimeter or two. If you can also use rubber/foam washers or gasket to minimise vibration transmission, this helps more. But if you can only use metal washers or something, there is still a benefit to spacing the fan slightly off a grille or slightly off a heatsink.

I tend to prefer the chromed wire kind of grille above all others where a grille is necessary, often you can bend the legs of these to sit it a little higher. Also where a close size exists, like 70-80 or 80-92, you can get the close size up, and adjust the "legs" to get it 5mm away from the fan... this is excellent for lack of noise. The profile of the wire makes less noise than sharp stamped edges also when you have to have it close to the fan for space reasons. On my "pet" systems that I'm going to have on a lot and near me, I cut the stamped grilles out of the cases and PSUs completely and just put the wire ones in.

I tend to pick PanaFlo fans myself, I tend to regard Noctuas as the "Apple" of fans... overhyped, not doing anything really different, and having a rabid fanclub that doesn't talk sense. Also happy to find surplus Papst, Comair Rotron etc quality industrial fans. Mostly I avoid buying from PC hardware suppliers, they tend to have a 80% price premium just for having the right plug on and are usually crap or rebranded crap.

paradigital wrote on 2024-12-10, 18:25:

Never was that enthralled with Noctua fans, but the 40mm noiseblockers I have seem quite good.

I replaced all the 40mm fans in my Cisco CCNP lab kit with these and they have been silent, even back when the “cab” was an Ikea LACK next to the head end of my bed!

BitWrangler wrote on 2024-12-10, 18:49:

You always get some noise from the more compressed air at leading edge of fan blade or underside trailing edge hitting static ob […]
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You always get some noise from the more compressed air at leading edge of fan blade or underside trailing edge hitting static objects in immediate vicinity. This is made worse by number of edges. So right on top of a heatsink is worst case scenario, as is right next to a grille.

Fortunately however, this is MUCH reduced by increasing spacing a mere millimeter or two. If you can also use rubber/foam washers or gasket to minimise vibration transmission, this helps more. But if you can only use metal washers or something, there is still a benefit to spacing the fan slightly off a grille or slightly off a heatsink.

I tend to prefer the chromed wire kind of grille above all others where a grille is necessary, often you can bend the legs of these to sit it a little higher. Also where a close size exists, like 70-80 or 80-92, you can get the close size up, and adjust the "legs" to get it 5mm away from the fan... this is excellent for lack of noise. The profile of the wire makes less noise than sharp stamped edges also when you have to have it close to the fan for space reasons. On my "pet" systems that I'm going to have on a lot and near me, I cut the stamped grilles out of the cases and PSUs completely and just put the wire ones in.

I tend to pick PanaFlo fans myself, I tend to regard Noctuas as the "Apple" of fans... overhyped, not doing anything really different, and having a rabid fanclub that doesn't talk sense. Also happy to find surplus Papst, Comair Rotron etc quality industrial fans. Mostly I avoid buying from PC hardware suppliers, they tend to have a 80% price premium just for having the right plug on and are usually crap or rebranded crap.

Thanks for the input.

I have been trying to replace the fan on my Abit NF7-S 2.0 northbridge heatsink with something that is as silent as possible because I use the system for testing and benchmarking parts and it sometimes runs for hours.

I just installed one of the Sunon MF40101V2 fans onto the northbridge heatsink with silicone washers between the fan and the heatsink and between the fan and the metal cover... and it still resonates.

I expected as much though, since it was resonating in free air too. If I just hold the fan sideways on my desk with my finger, it makes the whole desk resonate... the same as with all of the fans I have purchased for this purpose. A couple of very old and worn out fans I have that make other noises actually do not resonate as badly as any of the ones I just purchased.

I think it's slightly quieter than the possibly knock off Nidec UltraFlo fans I returned to Aliexpress... but it should be for four times the price per fan, from a reputable reseller! This is getting so annoying...

I paid $24 to ship three of these stupid fans. The Nidecs from Aliexpress actually looked quite high quality when I got those... these Sunons look surprisingly cheap and simple. Sadly, both are far too annoying for me to use on any PC projects.

What is with these fans??? 😕

(Also, DigiKey's return page makes the process look like a huge pain in the butt...)

EDIT: I have attached a crummy recording of the Sunon fan attached to my NF7-S with silicone washers, as described above. This was about 3 feet away, taken with a cell phone. In a quiet room it is this audible everywhere in the room... sorry just realized the volume level on this is really low. Recording sounds with a phone is nowhere near as intuitive as I would expect it to be.

EDIT2: Well, I reported the fan issue to Digikey and later that evening received a notification from my payment method that Digikey was sending me a refund for the price of the item + tax. So, for the cost of shipping and an embarrassing amount of my time, I now have three supposedly great 40mm fans that vibrate like mad. Yay? I'm just glad the process went fast. Nothing like wasting time finding the perfect product, wasting time trying to implement it, AND wasting time trying to return it. I actually never even received any confirmation or anything from Digikey. They just went straight to refund...

One issue I find with 40mm fans: nearly impossible to find the good older 3300 - 4000 rpm ~4cfm used on many older 86 and pentium HS for reasonable, all those recently found are about $10 each UGH !
Was lucky some new 50mm are 3500 rpm and about 7-8cfm, very quiet and more than enough air for pentiums and p.pro's if the HS can fit a 50mm...

I bought two 50mm Gelid Silent 5 fans to use and they're super silent compared to older fans, but were recently discontinued. Shame, because they're high spec (4000 RPM, 13 CFM)

Large fans are quieter and better.
Good airflow in a case is more important than more fans.
Passive cooling on a power-hungry hot GPU is a farce. It will make everything hotter and the other fans will have to run faster and louder.
Standardized watercooler mounting in modern cases is a welcome thing.
No, you don't need to 'refresh' thermal paste on a regular basis, if the thermal paste is of reasonable quality and has been properly applied.
Lubricating fans sometimes works.
In terms of cooling/noise/price balance, the Scythe Mine Rev. B is the best CPU cooler of all times.

I'm beginning to understand why the cooling solutions for actively cooled graphics cards were seemingly so bad for so many years.

Also, I was tinkering with a Geforce 2 GTS recently, and the card had signs of use and dust in the fan. When I tried to run the card the fan made this terrible groaning sound and was clearly not happy. I figured the fan was toast, but I removed it from the card, pulled the little C-clip off the fan shaft, pulled the fan off of the housing, cleaned it all out and added a touch of 5w30... and it spins FLAWLESSLY. It is nearly silent, makes no weird "tick" sounds, and pushes plenty of air to keep the card cool.

This was a simple sleeve bearing fan from ~2000-2001.

Contrast this with sealed ball bearing fans. If the fan starts making noise you have basically no choice to improve it: replace the bearing.

I didn't realize until recently that, IN GENERAL, ball bearing fans really should not be oiled. If you have ever had a fan go from "okay, but a little noisy" to "random ticking or loud scratching sounds" after oiling, it is because you have removed the friction between the fan shaft and the bearing, and now the steel shaft is spinning on the inside of the steel bearing rather than allowing the bearing (which is filled with balls) to do the spinning. This surface is not meant for this, so you will get lots of undesirable noises this way. I did this recently and thankfully I was able to clean the oil out and get it back to it's usual "old but usable ball bearing" sound. In a sense, by attempting to oil fans with sealed bearings, you are turning it into a sleeve bearing except with a steel sleeve that will randomly slip on the ball bearings from time to time as well... not ideal!

Some fans have replaceable bearings that can easily be popped out, but even then you have to be careful what bearings you buy.

I knew nothing about bearings a couple months ago, but I learned recently that there are several things to look for when buying bearings, most of which especially apply to fans that need to be quiet. Here is what I have learned:

• Bearings are usually listed with a number that specifies the size, but the number doesn't indicate the actual measurements of the bore (shaft) diameter, outer diameter and width (a 693 bearing is 3mm x 8mm x 4mm respectively), so you'll probably need a chart like the one on this page to figure out what they are.

• Bearings also usually have two letters at the end to indicate how the bearing is built. A "Z" indicates one side is sealed (meaning, the metal balls aren't visible from one side). A "ZZ" indicates that both sides are sealed. Most computer fans seem to be "ZZ", likely due to dust and the fact that they aren't expected to be greased by the user. Open bearings are probably much more common in larger applications.

• Bearings have "tolerance" ratings that have to do with manufacturing. This is the "ABEC" rating. I have no idea who determines these or if anyone enforces this, but I got some bearings that were ABEC-1 without realizing this was a thing and they were HORRIBLE. Very likely, they were defective, but if the manufacturing tolerances are at the low end, it seems logical that there would be more defects. ABEC-7 or ABEC-9 should be better quality bearings... but again, who is checking them? It's probably a roll of the dice, but I got some ABEC-7 instead and they worked perfectly.

• Bearings can also have noise AND vibration ratings! This one almost slipped past me before I ordered the second batch. This page seems to have a decent explanation of it, but I keep finding conflicting information about which rating is noise and which is vibration. Basically the ratings are V1,V2,V3, etc... (V3 being better), and Z, Z1,Z2, Z3, etc... (Z3 being better). The standard for each rating varies depending on the bore size (size of the shaft going through the center of the bearing). Larger bore = higher acceptable ratings for noise and vibration.

... if only all ball bearing fans were built so that the bearings could be replaced. Sadly, the vast vast majority I have found have them permanently adhered to the fan in some way so the whole thing is junk if the bearing goes bad.

For CPU heatsinks I really like how Noctua supply mounting kits for earlier sockets free of charge.
I've only done it once for a LGA775 board, but the process was painless, just a photo of the motherboard and the receipt for the heatsink which I got new off amazon.

I got some Corsair fans few years ago, Won't be doing that again. much cheaper build then some lesser brands that I used previously.

brian105 wrote on 2024-12-10, 20:09:

I bought two 50mm Gelid Silent 5 fans to use and they're super silent compared to older fans, but were recently discontinued. Shame, because they're high spec (4000 RPM, 13 CFM)

Good to know ! Digikey still has some in stock.

Now that I think about it, it would feel wrong to not mention Thermalright in this thread.

I am not really one for "brand loyalty" but Thermalright has consistently provided great products with incredible value, so all of the coolers I have used in my main PC have been Thermalright going all the way back to the SK-7 (with a Panasonic Panaflo 80mm) that has been reliably cooling my Abit NF7-S for something like 22 years now. I also still have my Thermalright XP-90 from ~2004 cooling my Athlon 64 X2 4200+, Ultra 120 Extreme from ~2007 cooling my i5 2500K, ARO-M14G from 2019 cooling my Ryzen 5 3600 in my HTPC and a Frost Commander 140 cooling my 5800X3D (last two are total overkill).

So, I guess what I'm saying is... if you need a good quality heatsink for any platform, finding a compatible model from Thermalright is always a good option. The main downside is that anything more than 5 years old probably won't have any branding on it, so it makes them hard to identify without packaging unless you know what they look like.

... hmm... I wonder if my brother still has the XP-90C he got back when I got my XP-90. That thing was an absolute behemoth at the time, being made entirely of copper.

Well, I stand by my original comment: If you need a quiet, vibration-free small fan, get a good quality sleeve bearing model.

I can't say whether this is inherently a problem with the bearing design, or if fans that are built for higher RPMs and longer life just tend to have other aspects that make them vibrate more.

I bought a pile of possibly used or freshly pulled Sunon KD1204PFS3 fans for dirt cheap, some with connectors (all wired backward for my needs, but easy to swap pins), some without... and so far all of the ones I have tested have maybe 10% or less of the vibration that the brand new Sunon vapobearing fans have. The difference is, honestly, STAGGERING.

Of course, these are lower RPM (4200RPM +-1000RPM vs 5800RPM +- 870RPM), but the difference is noticeable far below their max RPM. Even if I just blow at the fans briskly the Vapobearing fan has a very pronounced vibration in my hands, whereas the old sleeve bearing fans have zero. Also, the CFM is still more than enough for cooling old video cards and chipsets.

The sleeve bearing fans probably need a drop of oil since they're older, but this is absolutely nothing and takes only seconds per fan. The vibration issues with the vapobearing fans are literally unfixable... if they vibrate, you either use them in an application where that doesn't matter, or you don't use them at all.

I have some of these sleeve bearing fans just chilling on my desk, hooked up to a 12v power brick for testing and I keep forgetting they are even there. They are audible but not irritating, and there is so little vibration that they aren't even sliding across the desk. All of other fans I have tested have basically walked themselves across the desk until they tipped over within a minute of turning them on.

I will definitely be putting one of these on the chipset of my NF7-S. For those interested: These obviously don't fit down inside the round heatsink, but the heatsink has the same hole spacing as a 40mm fan, so I can use long screws to put the fan over the heatsink and even put the original Abit grill over the fan to keep a similar look. To not have to listen to (or keep replacing) one of the little slim stock-style fans, will be fantastic. 😀

EDIT: Only issue I notice so far with these Sunon KD1204PFS3 fans is that the wires are kind of sandwiched between the layers of plastic, so you'd have to cut a bit of the back cover away to solder new wires. Not a huge deal, but worth noting.