Reusing IBM System x3650 M3 backplane 69Y0650 outside of IBM system

[logan893]

I was hoping to reuse backplanes from an IBM System x3650 M3, backplane FRU 69Y0650 (8x SAS via 2x SFF-8087) and power cable FRU 59Y3459, outside of the IBM server.

I hope I don't need to connect the "configuration" port (cable FRU 69Y0648), and that the backplane works with SAS3008_IT-flashed M1215 HBA in a non-IBM/Lenovo system.
Has anyone had any experience with this?

Does anyone know the pinout of the power connector?

The ground, 5V and 12V are easy enough to find (by continuity testing through the SAS/SATA power pins), but there are two pins from the power connector that I only find connected to Vcc of an EEPROM (24C02WP) and nothing else (that I have found). The EEPROM seems to be fine with anywhere from 1.8V to 5.5V as input, if it is even needed. Also doesn't seem to be any 3.3V for the SAS/SATA connected at all, which should be fine.

Pinout (on the far end of power cable, 7x2 molex):
G 5 C G ? G 5 G C G C ? 5 G c (G=Ground, 5=5V, C=12V, c=Connector Clip, ?=Vcc of EEPROM 24C02WP)

 

[logan893]

Adding an update and practical test results to my own question.

I modified the 7x2 molex power connector, disconnecting the leads and hooking them up to one leg of a SATA power Y-splitter. Backplane works just fine with SATA drives (I currently have no SAS drives to test with) from what I can tell, both with the SAS3008 card as well as connected to a 4xSATA-providing SFF-8643 port on my ASUS P10S-I motherboard.

I tried both with and without power to EEPROM and I couldn't tell any difference. I settled for leaving it connected, hooked up to the 3.3V line.

I'll now be able to expand my tiny case with 8 additional 2.5" drives fairly easily. It's a snug fit, where the backplane metal bracket slides under the motherboard. I wrapped parts of the backplane in several layers of kapton tape to avoid any potential shorts, but I will add a few more layers of electrical tape to make the fit even more snug and secure.

So far I'm testing it with two HDDs in a mirrored zdev, including running the solnet-array-test-v2.sh script.

Hot-swapping works too, but drive accessibility with it all mounted snugly makes it highly impractical or even impossible with more than two drives.

Need to eventually figure out a more long-term secure mounting mechanism, but for now this works reasonably well.

Above the 2.5" drives and backplane as seen in the attached photo is a 120mm fan pulling air through 4x3.5" hot-sway trays, so there is some airflow hitting them from above. Had hoped to squeeze in a slim 92mm fan in the front, but unless I mod the front panel and cut away the plastic to mount it on the outside, it won't fit.

 

[ascii-]

did you have any drawbacks with the setup?
i'm in a very similar position right now. https://www.truenas.com/community/t...age-747592-002-power-layout-connector.103064/

 

[logan893]

did you have any drawbacks with the setup?
i'm in a very similar position right now. https://www.truenas.com/community/t...age-747592-002-power-layout-connector.103064/

Works like a charm so far, only it's a bit tricky to access some drives without removing them all when there are 4-8 in there. It's a very tiny case. I might try to figure out a better and secure way to have the 2.5" drives mounted, but it's solid enough if I don't shake the server around. A 3D printed holder/bracket for this backplane's custom spacing maybe.