I've recently had trouble getting my PC to boot, bare in mind I'm new to the whole PC building lark. Anyhow, I had it working running Windows 10 Pro off an SSD. I went to change case but couldn't because I didn't have any thermal paste to remove and reapply the aio. I have finally managed to trouble shoot the cause of the PC not posting. Me being a dummy I forgot to plug in the 8 pin CPU cable. Anyhow, it now posts but isn't recognising the SSD which has windows pre installed. It was working before I cleared the CMOS
we have all been there with the cpu 4/8 pin, your not alone. you may find it might have reset storage type (ahci or raid), and for msi boards the boot configuration can sometimes block sata 1 and 6 as it expects a m.2/nvme to be installed.
if you need further help though please let us know