N54L could not found 5th disk.

[Lawman]

Hey Guys, 

I'm trying do the same Mod with my N54L. It is an old device if we can let it be performed some high-level performance. 

I have success install the DS2622++ DSM 7.1 on my N54L. There was 4 * 3T disk could be identify. I have few old SSD stick in my hand. I just wonder the N54L will not support for the PCIE splitting, But I found a card can support with one NGFF(Sata) & one NVME SSD. but the NGFF need connect with the 5th Sata port from mainboard.  

The card still on the way, I have another 2.5-inch SSD tray to be SSD cache for the raid. But I am facing the challenge is the 5th Disk cannot be identified in DSM. It is show connected in BIOS already. I also have flashed the MOD BIOS can show the south bridge setting in BIOS, But the 5th disk show in BIOS is the third Primary disk show in BIOS. 

I try to change the DSM Hard disk parameter, whatever for  

DiskIdxMap=0
SataPortMap=8

or 

DiskIdxMap=0000
SataPortMap=42

It still could not be found in DSM. Can any someone help to share the Hard disk parameter with me? or I need do some change in BIOS?