The primary design requirement was good performance re: cooling. It’s entirely possible that some of these fans are somewhat redundant.
The cooling performance of the HDD tower vs. the Mediasonic 3-Bay hot swap I use for drive qualification is hilarious. Where the hot swap drives sweat at 45*+ C (even if there is only a single drive in the center bay), the pool HDDs temperatures don’t rise above 30* C during scrubs or a full pool rebalancing.
Between the single 80mm fan on high for 3 bays and a very high static pressure drop, this hot swap system is a excellent disk broiler. But my use of if is temporary in nature so I call it good enough for the 2-3 days that the drives will be in there as badblocks and like scripts hammer them.
As for the HBA fan, that was originally on a different, small heat sink that I wanted to replace the HBA heat sink with. However, the HBA heat sink naturally is non-standard, and PCIe cards are supposed to extend over it. So I just unmounted the very flat fan from the new heat sink and screwed it into the HBA heat sink. It is a very slight interference, i.e. not screw holes, holding those bolts in place. But it works.
Is the system quiet - no it is not quiet but I cannot hear it either.
On further review of the fan scripts, I likely cannot use them because they appear to require that fan group A and B will hang off a single fan header, respectively. That’s not how I operate mine, I like to distribute fans around the board for redundancy. The power bus may be the same all around but for me it’s also about the hardware connection coming undone for whatever reason.
If I find myself with excess time, I will have a look at the script and see if I can modify it to address groups of fan headers on the SM board as opposed to just two. If it’s too complex, I’ll let it be.
" I grow old … I grow old …
I shall wear the bottoms of my trousers rolled. "
–TS Eliot from The Love Song of J. Alfred Prufrock
Just place the NAS where a bit of air flow noise is not noticeable. Compared to some rigs I have heard, this system is relatively quiet. But it could be quieter if I replaced the industrial versions of the Noctuas on the back end (2 x exhaust, 1 intake) with non-industrial ones. I may yet do that since the CPU is running ludicrously cool.
I guess you could deisgn your own fan zones/fan groups, maybe with some additional hardware, but that would likely require a different approach I believe.
Well, that was fun. SuperMicro has a manual for my board (MNL-1858) but said manual does not clarify which fans are on which fan bus. There are fan headers Fan1-4, FanA, and FanB listed… I will look into the BMC next since that is what’s controlling the Fan Speeds at the moment. Thank you again.
The IPMI guide is also somewhat underwhelming but that’s likely a reflection of the wide scope of SuperMicro boards. I have printed out the Fan page in the manual (47) and will look into the script once I am home.
I reckon you’re right re: the busses, as Fan 1, 2, 3, 4 are clustered around the CPU (see A,B,C,D below), while FanA, and FanB (E & F) are sequestered to the lower left motherboard corner.
