Hmmm, the big question here is, did you fech with it?
Seriously, though, I hope that you get to the bottom of it. My main machine, the Threadripper build, posted a few times but suddenly gave up the ghost. Turns out the 1200w PSU was shooting out 18 to 20 volts at startup on the 12 volt rail, thus shorting out the mobo, etc.
I now have a Core i7 10th gen on an ASUS 1200LGA board in the Cosmos II case, but it wouldn't post to begin with. Turns out one of the modular cables I provided the techie for the build wasn't for the 850w PSU. Once he removed it all was well and the machine posts/boots as it should.
Yup, computers can be the most finicky things at times, not to mention frustrating, so hopefully you track down the error soon and get the machine back on line.