I've just upgrade the motherboard, cpu and memory in my unraid set up, booted back up and the cache and one of my drives is now not recognised by the serial number in the array.

 

these are the correct drives as I've checked to nmy screenshot from before the change.

 

I don't want to lose any data if possible, so it would be great if someone could advise me the best way to proceed. New Config etc?

 

Diagnostics attached as well

tower-diagnostics-20200414-1210.zip

This is likely because your HBA has RAID firmware, it should be using IT firmware, doing a new config and checking "parity is already valid" should fix it.

Forgot to mention, there's a chance that the disk is not using a standard partition, if it doesn't mount after the new config stop the array, you should still be able to rebuild it.