Supermicro BPN-SAS3-826SEL1-N4 Backplane info

[nexox]

Update: Definitely do not buy this, the SAS connector spacing is not the same as the stock BPN-SAS3-826EL1 backplanes, and it does not fit in a regular 826 chassis.

TL;DR: Just don't buy this BPN-SAS3-826SEL1-N4, pay the extra $20 for a regular BPN-SAS3-826EL1-N4.

I wasn't paying close enough attention when I hit the buy it now button, so I'm going to make this version work, and since there's almost no information about this part on the internet, I'm going to add some.

First, this is from a specific system: 6028R-E1CR24L with Part List | SuperStorage | Products | Super Micro Computer, Inc., and for some reason it doesn't use standard 4 pin Molex connectors for power, it uses 8 pin PCIe connectors (note the little gap between two pins in the socket, that means it's not a 12V CPU connector.) While the power cables from the PDB are the same part numbers used to provide 12V to a GPU, the PDB actually puts 5V on a couple pins (image from an ebay listing):

I verified this with my board, tracing the power connectors through a couple MOSFETs to the drive connectors to confirm the PDB silk screen is correct:

Now I just need to cut up and solder some spare cables and install the whole thing to test.

 

[BlueFox]

Pretty certain they did that because the Ultra line (X10DRU, X11DPU, X12DPU-6, etc) also has those 8 pin connectors on the motherboard (dual purpose for backplane and GPUs). Needed something capable of driving a full 24 drive U.2 backplane, which could be 600W+ on its own.

Newer versions of the backplane (BPN-SAS3-LA26A-N12) actually have both Molex Micro-Fit and the standard 4-pin connectors to support multiple motherboards/chassis.

 

[nexox]

Pretty certain they did that because the Ultra line (X10DRU, X11DPU, X12DPU-6, etc) also has those 8 pin connectors on the motherboard (dual purpose for backplane and GPUs).

Except this one seems to require the 5V pins (I couldn't find two 8 pin cables I want to cut up so I've got to wait until next week to test,) there's no VRM that I can find. Plus as far as I can tell this SEL backplane was only combined with the X10DSC+ proprietary-form-factor motherboard for the 24 drive 2U system with the tilt-up center bays, that doesn't really fit much of a GPU.

 

[BlueFox]

Yeah, it is specific to that one. Makes cabling a lot easier when the middle drive cage physically moves.

The Ultra line used the BPN-SAS3-826A-N4 instead, which does have 4 pin Molex, but is still powered off the 8 pin connectors from the motherboard (which have built in VRMs). Always an option if you don't need the SAS expander.

 

[GCustom]

Except this one seems to require the 5V pins (I couldn't find two 8 pin cables I want to cut up so I've got to wait until next week to test,) there's no VRM that I can find. Plus as far as I can tell this SEL backplane was only combined with the X10DSC+ proprietary-form-factor motherboard for the 24 drive 2U system with the tilt-up center bays, that doesn't really fit much of a GPU.

Yeah, I've got one of those and just realized I made the same mistake, pulled the backplane off the shelf, and it's got a pair of 8-pin connectors instead of all the 4-pin on the last one I just finished. So I've got a spare for the loud server unless you've got luck with making the cables work in a normal SM chassis.

 

[nexox]

Hopefully I will have time to solder some adapter cables up tomorrow, I'm pretty optimistic about it all working out, but not entirely looking forward to taking my whole system apart to swap.

I have managed to get my 826 to run reasonably quietly.

 

[GCustom]

Hopefully I will have time to solder some adapter cables up tomorrow, I'm pretty optimistic about it all working out, but not entirely looking forward to taking my whole system apart to swap.

I have managed to get my 826 to run reasonably quietly.

Yeah, my 847 is finally almost done and is pretty quiet, but the one this board was built for... I haven't even started on that one yet. I'd hoped to put this backplane in the lower rear bays of the 847. Once this one is finished, I'll move to my 847 SFF and copy everything that worked before having to learn new techniques.

 

[whoknew123]

OP I did the same thing as you lol. I’ve returning mine for a non S model. Gonna cost me an extra 40 bucks but I’ll pay that to skip the headache.

I wasted 3 hours trying to figure out why my board wouldn’t boot with this backplane connected. Then I finally took a close look at the model number and saw the S.

 

[nexox]

I soldered up one adapter from two 4 pin Molex to one 8 pin PCIe and tested out the backplane sitting on top of my chassis with just one SATA drive and it worked as expected. I didn't get it to work with a U.2 drive, but I don't have an NVMe SFF8643 cable, just SAS, and that could be the problem (the disk does show up with a SFF8643 to SFF8639 direct cable, so it's not my adapter card or motherboard.)

The old adapters I cut apart to get the 4 pin Molex connectors had pretty badly oxidized conductors that did not want to take solder, so I'm not going to test those further, I'm going to find my pin extractor and crimpers to build the adapters properly.

 

[nexox]

Update: I crimped one adapter from two 4 pin Molex to the PCIe 8 pin and tested with the proper NVMe-rated SFF-8643 cable and my system detected a U.2 drive. Now I need to go do another 16 crimps with my questionable tooling and I can swap backplanes (right now I'm testing on top of the chassis with the SSD balanced on a stack of other SSDs to get it to the right height.)

 

[whoknew123]

Update: I crimped one adapter from two 4 pin Molex to the PCIe 8 pin and tested with the proper NVMe-rated SFF-8643 cable and my system detected a U.2 drive. Now I need to go do another 16 crimps with my questionable tooling and I can swap backplanes (right now I'm testing on top of the chassis with the SSD balanced on a stack of other SSDs to get it to the right height.)

That makes me feel much better about returning and spending an extra 40 bucks for a non S. I admire your perseverance though.

 

[T_Minus]

Well that's good to know, I have a couple of those 826 backplanes stashed for doing some updates, I guess it sounds like worst-case scenario is they are spares for my x10dru chassis with those backplanes already, which, if you are running that gen those chassis are much better than DIYing and buying the n4 backplane... but yeah, older mobo\cpu\ram\etc

 

[nexox]

but yeah, older mobo\cpu\ram\etc

I'm running newer, actually, X11, I just didn't plan ahead very well when I bought this chassis a year ago and now I can't resist the urge to keep upgrading it because I know once I get around to putting it into production I'm not going to take any time to swap components for the next 5+ years.

 

[nexox]

Finally got around to trying to install this SEL backplane into my 826 chassis and discovered that the SAS connectors are spaced slightly differently and only the right-most stack of drives will line up and work. Do not buy this for a regular 826 chassis. Also there are several sheet metal tabs that are probably intended for older backplanes, the SAS3-EL1 has cutouts to fit around them, the SEL does not.

 

[cscracker]

Thanks for sharing this. I did the same thing and bought 6 of these not realizing they were not the regular ones, and there's no returning them, so I will be making them work, too. I wasn't able to find the pinout anywhere else on the internet, so I wanted to thank you for posting it. For what it's worth, I was able to get it to line up in my 6028U-TR4T+ chassis, with some prying on tabs to make room, on the one I worked on so far. I've got 5 more to do once I get the power cables addressed.

I also don't recommend anyone buy these, but they were way cheaper than the regular model at the time of my purchase, which is why I went with this listing, not realizing that it wasn't the same part. It's only one letter different and easy to miss.

 

[nexox]

For what it's worth, I was able to get it to line up in my 6028U-TR4T+ chassis, with some prying on tabs to make room

I got the backplane to fit but the drive connectors didn't align, except for the right column of bays, the spacing between each column is a little bit smaller than stock (I held the original backplane and the SEL together and that made it pretty clear,) so the second-to-right bay could be forced to fit (probably not a good idea,) but the left half of the backplane wouldn't come close to fitting drives.