Identifying existing hardware in R630 & Which Pcie lanes could support pcie 2 external SAS ports.

Used Poweredge R630. Does not have any drives currently but has all caddies. Posts and was working properly when last used and connected. 

Looks like the previous owner removed a pcie card or 2, I've been unable to determine what it was or if it would be useful or necessary to replace. 

Trying to find a Dell or otherwise PCIE card that would provide 2 external SAS ports for additional storage/ connection to a JBOD array. Any suggestions on which of the lanes to use, and if a lane sharing a riser with another device would limit the bandwidth for accessing data? 

It looks like a 3x PCIE model and has both processors and ram installed (no drives currently). From the included pictures, which of the risers/ lanes would be best used to transmit that data without limiting the bandwidth of it? With an adapter, would I be able to accommodate for NVME drives, or would I still be limited to SAS/ SATA? Any suggestions on Dell or other pcie cards that would fit within the system and allow for this? 

Would appreciate any and all help 

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