HP Pavillion screen turns to black, computer light remains on, hard reset doesn't work

[Haitoku]

Hi, I have a Hp Pavillion Desktop 690-0029, and today when I was in the midst of using it, out of nowhere all the screens turned to black, like the computer went to sleep. I clicked the mouse and keyboard keys to "wake it up" and no effect. I notice the tower's light remains on, I can feel there's still humming sound within. I tried to press the power button and nothing happens. I also tried to hold down the power button (up to 5 seconds), but hard reset did not occur and again nothing happened. I am sure the monitors are working because now I plugged the monitors to another computer as I write this. I am afraid to pull the plug to restart it, and it has been 12 hours now. I do remember about an hour before this occurred, Windows asked me for a restart to finish an update, I think I clicked snooze or do it later. I am not sure if that is related. Thank you!

[itsmyname]

@Haitoku -- I think that your sudden shutdown was a total failure of the power-supply, or failure of the motherboard.  While you could remove a side-panel to view the motherboard, to look for any "blown" components, you probably don't know what to look for.   

How good is your sense of smell? When sniffing near the power-supply, do you get a smell of burning plastic, from something "blown" inside the power-supply?

It's time to take the computer to a qualified computer technician, for proper trouble-shooting & repair.

The Release Date for your model of computer was 28-May-2018.  So, unless you purchased a 4-year or 5-year "extended warranty", or you purchased the computer in the last few months, HP will not fix your computer for "free".