HDD Detection Issues on ASRock Extreme4 Z390

Hi all,

[URL=https://uk.pcpartpicker.com/list/CbCvMZ]This is my build.[/URL]

Initially installed and configured my SSDs in RAID 0 and installed Windows 10, no issues, but had to wait for other HDDs (Computer is a Plex Media Server).

Received 4 x 10TB WD HDDs in the "MyBook" format last week. I shucked the drives and put them into my PC as per any other drive, connected them up (Power had to be extended using splitters), connecting directly into the other Intel ports on my Mobo.

I initially connected all SSDs/HDDs onto the same "chain" coming out of the power supply. The SSDs showed up without issue in the UEFI, but the HDDs didn't.

I then connected the SSDs onto their own "chain" with the HDDs on a separate one, replacing the "chain" cable with the other that came in the pack. The same thing happened again, SSDs were present in the UEFI, the HDDs weren't.

I've since changed the HDD "chain" over to another socket on my PSU, but to no avail. The "Storage Configuration" screen on the UEFI just keep stating "SATA3_2 : N/A" all the way to "SATA3_5 : N/A".

My plan is to put these WD devices into RAID 10.

My thought was that perhaps I've damaged the drives when shucking them, but I was really careful and the chance of all 4 being damaged like this is remote.
To test this, I then connected one of the HDDs back up via USB and it's working without issue; so I know it's not the HDDs themselves (presume all, given one worked and they all worked fine before installation).

I've also tried connecting each HDD individually to the Mobo using the same power cable (proven working) as the one connecting the SSDs.

I thought it could be the format of the HDD as they were in ExFat as a result of being from MyBook, so I completely deleted the volume on one (the one proven working via USB) and it still doesn't appear in the UEFI screen.

I then tried the non-Intel Sata port to see if that was an issue, but it's the same story. No visibility of the standard HDD.

I finally put the SSDs into other slots on the Mobo, and they appeared without issue.

This says to be the issue is either configuration or power. Configuration on the motherboard somehow or the power supplied to the HDD isn't enough to spin the disks. Pretty stumped.