If, other then the black screen, it appears to be running and you heard the normal windows startup sound then try turning up the brightness (usually the Fn button + one of the F-keys) and if that doesnt work then shine a flashlight into it. If you can see the image on the screen then the backlight has failed.
MERGED QUESTION Question from Wayne55 : "Gateway laptop windows 7 Home prem OA Acer group /Model # ms2274 / s/n LX WDM02001013B24A42200 / BLANK SCREEN"
Was gave to me.deleted all person before items .put in mine worked a couple of times .then screen off. Took battery out .rams out .tryed everything suggesty.battery light blue.power button blue.came on twice saying hit f1. Did then was saying safe mode.others mode.then mouse would not move .just at a list please help.