XPS 9730 not recognizing Samsung 4TB SSD correctly

There are few methods you can check the new SSD status.  Use diskpart command and list disk should show each drive with its capacity.  A utility such as CrystalDiskInfo can also report SSD information and health.

When RAID is not use, you can change to AHCI/NVME following this process:

1. Click the Start Button and type cmd
2. Right-click the result and select Run as administrator
3. Type this command and press ENTER: bcdedit /set {current} safeboot minimal (ALT: bcdedit /set safeboot minimal)
4. Restart the computer and enter BIOS Setup
5. Change the SATA Operation mode to AHCI from either IDE or RAID
6. Save changes and exit Setup and Windows will automatically boot to Safe Mode.
7. Right-click the Windows Start Menu once more. Choose Command Prompt (Admin).
8. Type this command and press ENTER: bcdedit /deletevalue {current} safeboot (ALT: bcdedit /deletevalue safeboot)
9. Reboot once more and Windows will automatically start with AHCI drivers enabled.

@Chino de Oro​ Thanks for the reply!  Looking at diskpart and the list disk output, it sees my Samsung drive as Online and Size 465GB.  I'm afraid Raid is on by default, so if I change it that will require a re-install of the OS correct?  Is migrating to AHCI/NVME the preferred setting for this disk config (I don't need data mirrored between disks)?  

If you follow the guide from my post, you won't have to reinstall the OS.  The drive will boot as normal with AHCI driver.  

As for the Samsung drive, you can use diskpart to clean it and using Disk Management wizard to create partition at full capacity.

I appreciate the guidance @Chino de Oro !  I have converted from Raid to ACHI as you suggested, and ran a diskpart clean on the Samsung disk.  Still no luck.  If it helps any, even the BIOS sees the Samsung drive as a Samsung 980 500GB disk (when it is really a 990 4TB disk).  

A few other updates:  I tried running SupportAssist and downloading any updates - no luck there.  I installed the Samsung Magician, updated the drivers and even it sees my 2nd drive as a Samsung 980 500GB drive.  I think my next recourse is to call Samsung to have them lookup the serial number of my drive to see what I got.

You probably got a 500 GB drive.  Don't know how, but you should check with the seller.