It may be hanging trying to interrogate IDE drives.

Have you messed around in the cmos?

First thought is the HDD is dying / is dead.

That will happen when it is trying to read the drive, but it either is not spinning up properly or something has failed on the circuit board but not enough for the drive to not be seen at all.

Agree ! Most likely a failing drive. Try going into bios and disable the HD controller and set it boot to floppy first if it is not. Save a reboot and it should try to boot from a floppy disk...

I concur with the HDD issue. If it's getting stuck stuck, pop'er open and unplug the HDD, then try booting, see if it will make it through POST completely. If still no, we have another problem.

Are you sure the fans don't run? If we're seeing POST, at the very minimum, the PSU fan should be going. If not, we should start with that.

I'm guessing this computer had a distinctive fan whirr that's not there anymore?

Must open it, whatever the matter is.

Hard power cycle? Remove power cord, press power button to de-energize any capacitors , plug power cord back in as try powering on?

Next I’d look to try and reset the cmos. Clear cmos with jumper or removing battery. Restore defaults and re-apply bios settings.

If still no luck it’s time to start looking at components, like ram/power supply.

Micron were using Intel made motherboards I think, so looking up problems specific to that board model may be helpful.

thank you all for the suggestions! i had never opened the tower before, and a very strange thing i noticed is that it actually doesn't have an SDD inside it?? the OS is running off an SD card. (yes, there's an added SD port card in the motherboard) i'm remembering now that it would ask me "boot from [DRIVE]" everytime i started it up. i'm surprised it was able to install games on the computer at all! luckily, the nice man also gave me a "extra" SDD so i will install it and let everyone know what happens tomorrow 😀