Anyone experimented with a replacement Axe II lid for fan noise ?

lqdsnddist

Axe-Master
While thinking about the ongoing saga of fan noise (at least for some of us with older units) and having swapped out some fans myself, the thought occurred to me that maybe it would be easiest to mod the lid ?

One of the issues with using fans of different sizes is that your dealing with the 60mm standoffs (on early units at least) and that larger fans also need to be mounted further from the lid to prevent a vacuum effect.

Well, suppose one either replaced the lid, or cutout an opening where a fan went ? I'd probably go with getting a replacement lid as to keep the original for resale value, but you can pretty easily get a sheet of acrylic or aluminum to replace the lid.

You could then cut out a hole to prevent a vacuum effect, and maybe stick some sort of screen material over it. Would be very easy to stick some bolts through it to secure the fan, or even use the normal rubber mounts most fans come with, thus isolating it for the top lid.

This would certainly work best in a rack situation and not a bag etc, but it seems intriguing to me, and I haven't come across any real discussion of it. If I can get some time this weekend I think I might cut a new panel to size and experiment with some 80mm or even larger fans, and take some temp readings on the processors to see if any real advantages are seen.
 
I ended up using fan-cooled heat sinks on each of the CPU's, which were about $2 each at a local electronics surplus place. That let them run at about 6-8 degrees cooler as measured compared to stock measured by infrared thermometer on the CPU. I then also had some perforated stainless plate and made a new top for it, which reduced temperatures about 10 degrees more outside a rack, but I assume the reduction there is less inside a rack.

Quieter and cooler.
 
I did some experiments just using foamcore board (and its cheaper and easier to cut than acrylic or aluminum sheets) and some various sized fans and fan speeds; 80mm Nocta, 120mm Nocta, 120mm NoiseBlocker etc just to get some noise and temp readings.

Long story short - I think using an 80mm fan, instead the unmodded lid, proves to be the best solution in terms of absolute silence and keeping the temps at a level of around 90-95 degrees (they are rated up to 185 from what I understand)

Using a 120mm fan, drawing air from outside the case, spinning at 2000 RPM kept the temps lower, about 75 degrees but produced pretty audible airflow noise. Its moving about 75 CFM so that is a lot of airflow, HOWEVER, its not all directed across the heatsinks, but certainly does ventilate the rest of the case, and other areas which produce some heat like the power supply bits up front. All in all, a bit of overkill IMO

Using a 120mm fan, but spinning it at 1000 rpm or so, produced temps around 85 degrees, and was quieter, but still noticeable. Just not enough bang for the buck of having to mod a new case lid IMO

Using a 120mm fan inside the case really didn't give it enough air flow as it had to be too closely mounted to the lid and this suction reduced airflow to where the fan wasn't very efficient. 120mm fan simply needs to have an air intake. Likewise, there simply isn't room to mount any sort of funnel/venturi type of system on a 120mm fan to get it to direct more air across the heatsinks. Just no room, though that certainly would get air moving at a high rate across them.......

Best solution I found was a 80mm fan, mounted instead the case (I did have to cut off the 60mm bolts) to mount it. With the case lid on it gets much quieter as you'd imagine, and as the internal air really isn't that hot, didn't really produce that much better temps using an air intake, few degrees, but noisier.

Going to the 80mm fan over the best condition 60mm fan is probably the best overall switch you can make. The 80mm is small enough to still direct a good deal of airflow across the heatsinks, but big enough that it produces a higher CFM at a much lower speed.

I'm running a Nocta 80mm fan, using a resistor to spin it at 1300rpm, and with an airflow that feels similar to the 60mm's spinning at 3000 rpm, so obviously much, much quieter. Have to pretty much put my ear to the case lid to hear if its running.

Temps (which may not be absolute as I have no clue how good my laser thermometer is, but should be relatively accurate) are pretty equal to the 60mm fan.

60mm fan certainly does the job of adequate cooling, but just with a bit of a noise penalty. 80mm fan does the same job of cooling, but quieter. Cliff and Co. are pretty smart and I'm sure found this same thing out, which is why they are using 80mm fans in all the newer units. Rule of thumb, never doubt Cliff on anything, he ALWAYS knows best LOL

So, long story short, the best overall cooling, at the lowest noise level, is a high quality 80mm fan, spinning at a moderate RPM. Its going to keep the unit plenty cool under the most demanding of conditions, and do so basically inaudibly. There really isn't any need to run the chips 10 degree cooler and your just doing so at the expense of noise.

Perhaps kind of a "duh" conclusion, but always fun to experiment a bit and come up with one's own conclusions.
 
Have you moved away from your hair-tie solution? Also, did you mean Noctua fans as opposed to Nocta? I use Noctua in all my PC builds and they are always great and quiet.
 
Hair tie solution is still the best option I've found to help reduce the noise of the 60mm fan (stock or otherwise) without making any real mods to the case.

I had a bunch of other fans laying around (and too much spare time lol) so thought I'd see what else was possible.

The hair tie, or other suitable bands, did improve things, even with the stock fan though as less vibration was transferred to the lid, which acts as a sort of resonator it seemed. Its an easy one to do and doesn't require a single special tool, and you can return to the factory setup.

That said, moving to a 80mm fan is an improvement (which is surely why Fractal did the same) BUT... if you own an earlier Axe with the 60mm bolts, you don't have many options; either A) buy a new lid for $70 or B) cut off the bolts and mount a bigger fan with new bolts which you can either drill through the lid (doubt many like that) or JB Weld new ones on.

I went with the JB Weld method, but I'm actually not mounting the fan onto the bolt shafts, instead, I'm using little tabs on each bolt/rubber spacer, and then attaching the fan, using the silicon inserts into the tabs. This way the fan is well isolated from the lid, yet still quite secure with nothing to worry about stretching (as some had concerns about with hair bands)

Basically, the best possible way to mount a fan is using the silicon inserts they come with, but there was no way to do that with the mounting bolts, so I had to think of a work around. I'll share some photos of that project when I get a chance.

Also, yes, typo, meant Noctua. Cost a few bucks more than other options, but what's a few bucks when its going into a $2300 Axe-Fx right ?
 
I had FAS replace mine years and years ago with the 80mm fan lid. I have no idea what kind of cost was involved as it was in for a new PSU and I had them mod the humbuster output for a lower noise floor.
 
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