Does it have a mind of its own?

mine does this on occasions when i have it tilted too far up in the air on the tilt mechanism on the bottom of it, think the connection has been pulled too many times over the years,

hey ersmommy
I think you should check the connection between your moniter and mainframe and the power line, maybe it's a imperfect contact or lower voltage. If the connection is ok, the second step is you should find another monitor to replace yours and check your monitor is broken or not, if the replace one is work maybe yours is broken and if it's not the third step you shuold replace your mainframe and change your old monitor back to ensure that is the problem, after replaced your mainframe, if your monitor is gonna work, maybe your viedocard has something, you could reinstall the videocard driver or use the repleace method as above.
Have a good day!

My TV just did the same thing to my mom last week. My mom and sister were over at my new place, and my mom plopped down in front of the window, since I have such a great view of the parking lot. We were joking about how my late great grandmother used to sit in the window for hours at a time, just watching what went on on the street. All of a sudden, the TV went off. My mom lent over and tried to turn the TV back on. It came on for a minute, then went off again. She did this a couple more time, and each time it had the same result. My sister says "That was Mama Audrey (grandma). She said 'Y'all ain't watchin it, y'all in the window" lol

One time my grandmother was learning how to use the internet and she was just clicking random stuff pretty fast (and it was a pretty old computer so it got really bogged down) and suddenly a message thingy popped up and said something like "It seems like you don't know what you are doing. If you need help, call your local technician or a toll-free internet help line at (whatever number it was). She freaked out and thought the CIA was watching her actions... XD It was pretty funny, but I've never seen that message before and I can't get it to come up again.

LOL. That is funny but it could get annoying also. I have a touch lamp that likes to turn itself on sometimes. I also have a fireplace insert too and it turns itself on sometimes also. I think it is due to power surges.

Now that would be spooky..lol my moms monitor does that. Maybe the sleep button was pushed on accident and maybe that kicked it off or you really do have a spool in your computer.

they do like their sleep.