Supermicro X10DRT-H and PCIe x8 in x4

[tomas.holy]

Hello,

I'm looking for more information on a specific issue I've encountered with Supermicro Twin server, model 6028TR-HTR, which contains 4 nodes. Each node has an X10DRT-H motherboard, equipped with two PCIe ports labeled SXB1 and SXB2. According to the manual, these ports are "PCIe x8 in 4x".

I've attempted to use these ports with a riser card and a adapter for NVMe SSD, as well as directly connecting the adapter without a riser card, but the booted system does not detect the NVME. It seems these ports may actually be a proprietary connector with a different pinout than the PCIe specification suggests, as the physical size is PCIe 4x but it's supposed to support 8 lanes.

After extensive research, I found that this slot is intended for "Supermicro storage add-on cards", and I located a specific riser card, BPN-ADP-SAS2-H6IR, with a SAS controller for this port.

I'm curious if it's possible to find the pinout for this connector. I have the opportunity to get these servers at a very good price, but I need to connect NVMEs to these slots. I still have some time to explore and experiment before giving up on this idea, so I'm wondering if there's any additional information available.

 

[sko]

SXB connectors are usually only intended for supermicro risers or proprietary adapters (e.g. the node interface card). They don't have standard PCIe pinout, hence they are also not labeled "PCI" but SXB...

Just contact SM support for part numbers that are compatible with those connectors.

 

[tomas.holy]

Just contact SM support for part numbers that are compatible with those connectors.

Thank you for the response. Yes, I just received a reply from support confirming what you mentioned: the SXB connectors are indeed intended only for Supermicro proprietary cards. Interestingly, I've discovered a riser card, RSC-R2UT-E8E16R, that seems to be exactly what I need, except it doesn't fit into a 1U form factor.

So, it looks like my only option is to reverse engineer this riser card and get a custom version made at JLCPCB to suit my needs – just kidding, but it's an amusing thought!

SXB1 was used either for the models of this system with a SAS controller, or for a proprietary network card, AOC-PTG-i1S.
SXB2 was intended for possible 2U risers, but it’s not a standard form factor.