ok well... theres some stpes u could try.
first off. that light indicates ur monitor is in sleep mode. in other words, its not getting any signal at all or its getting a singal telling it ur computer is in sleep mode and it should be too.
so to see which is the probalem. 1. plug it into another computer and see what happens. does it work? if so, the monitor is NOT the problem and its working just fine.
if nothing happens, the ur monitor is to blame. woo-hoo! easy fix!
if its the monitor, take a look at the tiny pins at the end of the cord. (the tiny metal things in the plug) and see if any are missing or bent. if any are bent, then take a falt head srew driver and CAREFULLY bend them back to were they should be. plug it back in and it should work.
if any are missing, then ur monitor wont get a signal and will need a new one. good news? thats what the salvation army is for. u could get one for $3 there.
now... if the monitor works in another computer, then its ur computer thats the problem. in which case, once again there could be many things wrong.
so....
is the computer seeming to work? is the power lights, hard drive lights, and fan on? if u have speakers, does the windows login sound play (assuming u dont need a password)?
if yes, then its the card. the video card.
now.. if thats the case, look at the port u plug the monitor into on the computer and see if anything is in the holes. if there is, try to get it out. if theres not, then......
either ur card is shot and u need a new one or.... its not properly connected (loose).
soo... open up ur computer and make sure the card is succurly seated (pushed all the way down) in the slott.
if ur card is attached already to ur motherboard and not in a slott skip that step.
if it still isnt working then ur card is bad. simply but a new video card, try ebay, and install it.
now.... lets assume u answered no to when i asked "is ur computer seeming to work?".
then something is preventing ur computer from booting. which could be a whole other issue.
soo.... if u have another monitor, plug it in and see if that works. if soo. see where i stops working (the computer)
does it give an error? does it go through the self test (post) when u turn it on? is windows causing an error?
without knowing if it loads windows or stops before loading windows, this is where the hep would end and ud have to let us know which it is.
sorry this is so long, but i wanted to give u all the steps u could try to see whats causing this to happen. and sorry if i spelled wrong, i type fast and dont look at my screen and i never spell check.
hope that helps.