Question Mobo rapidly rebooting (flashing) after power run out ?

[TommyTheNightmare]

UPDATE

I've tried a different PSU today and it happened again, so it seems like either the mobo is damaged or it was a CMOS issue. I've cleared the CMOS and booted with the actual PSU and it didn't happen again, so I'm pretty convinced that it's something about the mobo.

Built a new Hackintosh yesterday so I replaced the CPU fan and installed a new SSD for the hack.

PC Specs:

• i5 9600K running on Gigabyte B355-M DS3H
• Asus Tuf Gaming 550W PSU
• RX 560 4 GB
• 1x PCI-e Wifi-Bluetooth Card
• 1x NVME M2 SSD
• 1x 2.5" HDD
• 3x 2.5" SSD
• 4x case fans running at full speed at all times
• CPU cooler with a single fan.

I turned it on, it rebooted itself once before POST (it does that when left unpowered for a while) and it started powering on and off rapidly and when I mean this, it was literally flashing on and off at like 2x reboots per second. I know what a boot loop is and it defo wasn't that. See the videos below to see it in action. This happens the other day on Sunday night.

#1 - Shuts itself down and gets stuck on the boot loop on its own:

http://imgur.com/a/y1HDSxH

My first thought was that the front panel IO cables were upside down and causing a shortage so I did re-connect them but they were correct. It did boot fine after that and was working fine the morning after.

But it happened again this afternoon after a power outage in town so I removed all of the front panel IO cables and checked inside the case to see if there are any cables touching or something but everything looks ok.

Except for the fact that my 2.5" HDD is now touching the metal case due to its new mounting position.

This is how it was mounted after I installed the new Hackintosh SSD:

http://imgur.com/a/GdCZzJV

That HDD is mounted on the SSD mount walls due to its size. Prior to the new SSD I've installed the other day, it had a silicon rubber frame wrapped around it so its metal parts weren't touching the case up until now. But I had to move it to the bottom slot and had to get rid of the rubber frame cuz it wasn't aligning with the screw holes. As seen in the images below.

How it was mounted with a rubber frame prior to the new SSD:

http://imgur.com/a/GICHj4Z

Afterwards:

http://imgur.com/a/eUTjXVv

Anyhoo, I removed that HDD and noticed that the metal part on the center of the PCB was indeed touching the chassis so I put it in a plastic portable HDD cover and installed it back in, but the issue was still there even worse this time.

At this point, I'm pretty sure it only happens after the mobo runs out of power and loses the CMOS/BIOS state as it was booting fine this morning.

#2 - This is what happened after I re-installed the HDD with a plastic cover:

http://imgur.com/a/f7HgZeX

As you can see, shutting down from the PSU switch button didn't end it this time, thus I called it even worse.

I waited for a bit after that last video and it has resolved on its own, I'm currently writing this post on that machine. Took a screenshot of my current voltage reading for you guys;

http://imgur.com/a/sMkMkQm

My question is, I probably shorted my PSU or mobo due to HDD contact with the chassis (if that's possible at all) so does it need replacement or is something else going on here?

Also, why does/would this only happen after the mobo loses its CMOS/BIOS states and not when BIOS and CMOS power is intact? Because I can assure you that HDD was still working like a charm yesterday before I was even aware of this stuff, I even played a game on it.

Last of all, am I safe to keep using this machine for now or should I stop immediately to avoid data loss on my drives? (most crucial drives are connected to this one)

You can see my specs above for the current power draw, any help is greatly appreciated.