Question Anyone Seen This One... Deader Than Dead

Feb 1, 2022
2
0
10
Hi everyone!
I've been around computers for decades, worked at IBM 15 years, built many computers over this time, and I have NEVER seen this...
The system in question, one I built some years ago:
MSI Z97 Gaming 7 motherboard
8GB Corsair memory
Kingston 500MB SSD with Windows 10 installed
2 x 2TB Seagate SATA hdds

The other day I go to power it on and it basically said "no soup for you". The system started up and then powered off within a second, then started itself back again, and a second later, powered down, rinse and repeat.
I happened to have a new, never used power supply so I removed the old one, cabled up the new one and it did stay powered on. Good news I thought... Until no OS booted.
And even worse, none of the 3 hdds were seen by the BIOS. It was if they weren't there.
I have 3 other computers and I attached each of the hdds (one at a time) and in each case the hdds may as well be another brick in the wall - I would've gotten the same results.

So, any ideas what may have caused a previously good 3 hdds to be wiped out to such an extreme? Virus? Hacked? The absolute worst luck in HDD history?
The motherboard still boots to the UEFI/BIOS and if I attach a different hdd (one that was laying around collecting dust) it sees it. Even with the original SATA/power cables...

thanks