Why won't my 42 Inch Philips Plasma turn on?

my tv has gone exactly the same and i think it is because i pluged this old computer into it last night the i turned the tv over to watch some sky then i got tired and turned it of then this mornig i went to turn it on and the blue light came on but no picture or sound so i unpluged it and put it back in and the stanby light came on but this when i went to turn it on nothing happend not even the blue light came on it dosnt work on the remote or power button

gage murphy
September 2009