Strangest problem with my computer yet

I have a reputation for having a kiss of death with computers, but at least I have a good adviser on how to fix the problem usually; but this time, not even 40 years of experience has any idea what's wrong.

Last night everything was a-ok, but this morning I found my computer off. I turned it on and a loud beep from the small speaker in my mobo emitted for about 3 seconds. My monitor's light is blinking like it isn't getting any signal.
All my lights and fans in my case and component are functional.
I checked my hard drive to see if it was broken, it wasn't.
Nothing is blown ALTHOUGH, last night I heard a loud noise, like a cap gun went off in my ear nad it came from the direction of my computer. It was still working after that, and it may have been from something else, but who knows.

Please, please help.

A capacitor or another component probably blew. Carefully inspect the motherboard and if it looks fine, try a different PSU.

If you don't see anything blown, then it might be in the PSU and I definitely don't recommend that you open it up to verify.

do you have another that you could test with? if another one makes the computer work, you need a new PSU. Also see if you can find out what the error codes and lights mean in the manual for you MOBO.