LSI-9200i + x399 Designare EX - SAS not detected

Hey guys. I’m a newbie in this, so I have a question.
I ran into a bit of an issue.

I am running custom storage server.

Rig:

AMD Threadripper threadripper 1900x
x399 Designare EX
32 gigs of ram
random low power gpu just for troubleshooting. Mostly we connect to it via a network.

Recently I bought Seagate Exos X16 Sas 16TB Enterprise hard disk. Didn’t read the description, so didn’t realize it was a SAS drive before it came.

So I taught ok, and ordered LSI 9200-8i card.

I got an adapter for it, since the cable it comes with does not have the SAS connector, only SATA. That did not work.

So I ordered another cable, thinking maybe the adapter didn’t work. I got the Startech Sas808782p50 mini sas cable.

Connected that one to the LSI card, to the Exos drive and to power. But nope, still nothing in the AVAGO settings.

Not sure how to troubleshoot it at all. I do have one drive that is connected to the LSI through the original sata cable that comes with the card, and it works great.

The LSI card is flashed to the latest firmware IT mode.

What can be the reason it does not detect the Exos drive? I tried the avago settings with only the exos drive, still no luck.

Any help would be great!

What adapter did you buy? SAS drives can’t just be ‘adapted’ to work on SATA ports.
You probably need to cut or remove the 3.3v line from the SATA Power cable (the same power cable that attaches to power a SAS drive, yes yes)
It is the wire closest to the notch in the connector.

Hey, thanks for the tip, but no adapter is being used now.

I have the Startech Sas808782p50 mini sas cable, that connects to the LSI card and the EXOS drive.

Theoretically should work like that. But nope.

The adapter question was separate, only because you mentioned some kind of adapter. You probably still need to do the 3.3v modding

Yea the adapter was the one I initially used. Not sure I would go as far to mess with the pin layout. But thanks for the info!

Only modify a power splitter/extension. Modifying a stock psu power cable is optional. Never ever modify the pins on the drive.

Yea it would seem you responded without actually checking the whole thread.
I have no idea why you mentioned socket compatibility?

Anyways we solved it by switching the board and the CPU out. We are no longer using threadripper. It would seem that either Threadripper 1900x, or the designare x399 mobo don’t support SAS at all. We switched to a r5 5600g and it picked up the drive without any issues.