Dell PowerEdge r640: on board SATA ports

 Often times I choose to utilize the onboard SATA port on my servers.  Usually it is because I want the boot OS drive to be something outside of the RAID controller.  Maybe it is because all of the drive bays are in use for data drives, maybe it is distribution of I/O load, being less reliant on a specific controller, or even simplicity.  

On the Dell r640 is has a "new-ish" connector.  SFF-8611 Cable OCuLink  I have seen them in use in SuperMicro's.  I guess these are intended for PCI-e communications, however Dell decided to use them for SATA connectors.  That being said I was able to track down a "Oculink PCI-express SAS SFF-86114i To 4X SATA Server High-speed Conversion Cable".  This did not work.  I broke down and paid a premium to get a specific Dell cable.  Apparently the pin-out is different. On the r640, this would normally be used for the optical drive.  This particular machine didn't have a optical drive bay, so that cable didn't help me.  I did eventually find the  MB SATA cable PN 0VDHV7

In this case the SATA cable is leading to a combination PCIe-M.2 NVME & M.2 SATA card.  Due to the heatsink on the NVME card, there was only one spot to put the card.  The cable routing was tight but acceptable.