Supermicro 846 model questions

Jebusfreek666

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Feb 6, 2020
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I have been looking to convert my tower server into a rackmount for a while now, and have settled on the Supermicro cse-846. Most of my research led me to the models (or to buy aftermarket) with the PWS-920P-SQ power supplies in an effort to quiet this beast down. I have found one for sale (although very over priced, but they all are right now) with model# CSE-846BE16-R1K28B. This unit comes with the BPN-SAS2-846EL1 backplane, PDB-PT846-2824 PDU, and 2x PWS-1K28P-SQ PSU's. It also has the optional 2x 2.5" hot-swap bays in the rear, which I like.

My biggest question has to do with how loud this thing will be. It will be located in a closet in my bedroom, so it can't sound like a jet. I plan on replacing the internal fans with Noctua's throughout. But all the other builds I have seen use the PWS-920P-SQ and not the PWS-1K28P-SQ PSU's. Will this make a huge difference in noise levels? Also, will this make a huge difference in the cost of running the machine? I have looked already and it will accept a Micro-ATX board, so it should just be a simple case swap from my current setup.

It does not come with rails, so if you have any recommendations as to rails to pick up for it, please let me know. Is there anything else you can think of that I should be looking into? This is my 2nd build (1st rack mount), with my first build being the one I am changing to this case, so I don't have tons of experience with this.

Thanks all!
 

Jebusfreek666

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Feb 6, 2020
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Rails: https://forums.servethehome.com/index.php?threads/supermicro-rail-failure.24953/

Noise: What's your thermal load? (What's going in it? Are all the front drive bays going to be full?) If you swap fans, the (obvious) tradeoff is airflow -- which is more of an issue if you're generating a lot of heat inside.
It will eventually be full of drives, but to start will only have about 12-15 (6-12TB WD shucked). It's not running much in terms of hardware as it is my Unraid/Media server. I will have a Mellanox 10GBe NIC, Quadro P2000 for transcodes only, and a LSI 9211-8i HBA. As for the rest of the internals I have the X11SSM-F MOBO with a Xeon E3-1230 V5 CPU and 64Gb of Samsung DDR4 RAM.

Also, I just read that post about the rails. Thanks. But do you have any advice on where to buy? I'm guessing supermicro charges a ton for shipping. And some of the ebay listings a kind of questionable if you will get the real deal or some cheaply made knock offs.
 
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i386

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Mar 18, 2016
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My biggest question has to do with how loud this thing will be.
"It depends"
If you use it as a simple fileserver with low cpu usage it will be pretty quite.
If you use a raid (software or hardware doesn't matter) solution with a too small strip size and no caching mechanism the seeking noise of many hdds can be audible and annoying.
But do you have any advice on where to buy?
Ask the place where you want to buy the chassis from if they have the railkits too.
(Imo it's worth it to get original supermicro rails :D)
 

eduncan911

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Jul 27, 2015
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The PSUs are the loudest pieces in these SC846s. I've had SQs, 1Rs, and the other one (I can't remember at the moment).

Even with the SQs, it's still the most noticeable noise coming from the box - once you lower all fans down to 0% idle via the ipmicfg tool, which I have done (most don't go that far though and complain about loud chassis fans). As a matter of fact, I have an SC846 sitting right next to me as I write this post on a hardwood floor in my large home office environment that is drop-dead quiet (the office being very quiet normally, that is). It has two 540SQs in it, but i only run one because, again, the PSUs are the loudest piece once you lower all chassis fans to 0% PWM. It's about the noise level of a small desk fan on medium speed, like those small 8" fans you can get from the store sit on your desk. Again, that's with only 1 SQ PSU running.

I have made another SC846 even quieter for a client by taking out the PSUs and PDU, and just installing a normal ATX power supply rated for very low noise. You also save about 9 Watts of power at the wall by removing the PDU and PSUs and going with a normal ATX Platium PSU (I've built a few extremely low-powered SC846s with all disks spun down at 55 watts at the wall). You can also negotiate lower shipping fees by asking the seller to remove the PSUs, which are pretty heavy actually, and they have PSUs to use elsewhere.

So if a desk fan running at medium speed is too loud for ya, forgo the whole SQs and just replace it with a normal ATX PSU. Use Supermicro's IPMICFG tool to lower your fan speeds down.

Oh... That's if you have a Supermicro motherboard, as they usually have IPMI remote controls. if you have another brand mobo, then most likely you won't be able to lower the fan speeds lower than 20% PWM in a normal BIOS. Asrock, Asus, and MSI are especially annoying in this regard (and I usually override them in my gaming desktops with speedfan - which you can't really do in Linux). In that case, then yeah replace the fans or build your own PWM controller that lets you set 0%.
 

Jebusfreek666

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Feb 6, 2020
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One more question about this model PSU. The unit I am looking at comes with 2 of the PWS-1K28P-SQ, but no power cord/plug. Is there any particular one I should look for online, or does it matter at all?
 

eduncan911

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Jul 27, 2015
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One more question about this model PSU. The unit I am looking at comes with 2 of the PWS-1K28P-SQ, but no power cord/plug. Is there any particular one I should look for online, or does it matter at all?
They use standard power cords. Though, at 1200 watts each, it will need to be a 14 gauge cord.

Also note, a standard AC outlet in the US can only supply 1650 watts on an 15A circuit @ 110VAC. A 20A circuit will get ya 2200W.

A single 1200 watt PSU is way way overkill for a sata spinning disk box with dual CPUs - that's all you're planning on.
 

Jebusfreek666

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Feb 6, 2020
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They use standard power cords. Though, at 1200 watts each, it will need to be a 14 gauge cord.

Also note, a standard AC outlet in the US can only supply 1650 watts on an 15A circuit @ 110VAC. A 20A circuit will get ya 2200W.

A single 1200 watt PSU is way way overkill for a sata spinning disk box with dual CPUs - that's all you're planning on.
I realize it's overkill, but those are the PSU's that come with this unit. I would prefer the 920p-sq's, but that wasn't an option.