8tb External recognized via usb but not internal sata

So I bought 2 WD 8tb external drives and copied my movie files onto both. The 4tb WD Purple hdd in my movie server died (still under warranty). My thought was to pull one of the 8’s out of the case and put it internal and use the other via usb as a backup. The server pc won’t recognize the 8tb internal at all. I can put the drives in their cases and plug them in via usb and both are recognized.

I assume the power requirements for the hdd are the same whether from an external drive or internal bare drive.

Wind 10 v1903; SSD on one sata; DVD on 2nd sata leaving 2 open sata’s for the 8tb hdd. Tried 2 power plugs and 3 different sata cables and no recognition by the PC.I even did a fullm format of the drive I intended to use internally.

Suggestions or thoughts?

Have you use Disk management to see if it list there?

I have. The system doesn’t see the 8tb drive. I pulled out a 640gb hdd (WD) and plugged it in and the system saw it fine. I then put the 8tb back in the external case, plugged it into a usb slot and the system sees the drive just fine. So something is going
on relative to the mobo (best I can tell) that is stopping it from seeing internal sata.

I’m a fairly high tech level and my son is as well so between us we have a higher than average amount of knowledge and experience and we are both stumped.

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