2008 Unibody MB...

[waloshin]

Has problem with the screen turning off after bootup. When the mb boots up and right before you can login on the screen turns off and you can't turn it back on.

 

[Detrius]

Is there still an image on the screen? That is, if you shine a light on it, can you see stuff? It's probably the backlight that's going out. If it goes in and out as you move it, it'll be the inverter cable. Otherwise, it's likely to be either the inverter itself or the LCD.