Just saw the video.  I'm not sure you're waiting long enough for it to actually start up.  I haven't done any timing but it seem to take a good 30 seconds for things to come to life and I'm not sure if you hooked up the backlight but it doesn't come on when the screen goes black on start  up.  It doesn't turn on until almost partial boot up.  I would say it take 5 or 10 seconds just to hear the hard drive come on.

Are you hearing this, at all?  It does look like normal start up until you remove power.

When you get the start up beep, wait at least 30 seconds.  Mine looks dead until it springs to life and the backlight is not on until then.

There's also a creaking sound, what is that?

Edit: for clarity, I mean "comes to life" AFTER the screen goes black and clears.  It's an old computer and it needs a little extra time to get moving