Did Sleep Mode kill my Monitor?

I recently formatted my HD and reinstalled everything. One thing I usually do that I forgot to was to turn off Sleep Mode. When I woke up the next morning my monitor was off. I turned on the power and the power light flickered then turned off. I've tried it on different outlets and even different PCs and it doesn't work. I'm using a secondary monitor from a Dell (I use HP) and it works fine but it's really small compared to my other one. I'm wondering if anyone has had issues with Sleep Mode killing their monitors, or if it was just my monitor's time.

lol no, sleep mode cannot 'kill' your monitor. But your monitor can 'die'. Plug it in to another source (like a computer) and see if it still works. Make sure the power cord is secure and the monitor-to-source cord (hdmi, dvi, etc) is secure all on both ends.

Is it plugged in to the motherboard or a graphics card?

Did you have a recent spike in power (perhaps a power outage)? Is your monitor and computer protected by a working surge protector?

You have a smaller monitor that works you said. do they both connect to your computer with the same cord? have you tried changing cords (all cords)?

I have tried the monitor on different outlets, using different PCs, and different cords. The Monitor's power light will flicker on for a second then turn back off. The smaller monitor works fine using the same power cord.

Both my Monitor and PC are using a surge protector

Sleep mode really doesn't do anything to the monitor, it blanks out because the video card output is shut off. I would have to say that it was merely coincidence that your monitor failed during that period.

Sounds like the internal power transformer is at fault, which generally means replacing the monitor as it's "not user serviceable" and difficult to find parts for. Monitor power supplies are not as clever as computer power supplies and I have seen a few go where computers have survived.

yep, sounds like your monitor is caput (especially since you can't use it on any computer)