I had a brand new powerbook...was perfectly working for hardly one day, but all of a sudden, when i open it from sleep, the display only comes fro 1 second, and blackens out...i can vaguely see it running in the background, but there is no enough light. I hae tried adjusting the brightness....nothing works...have given it back to apple to check. migt get a replacement...keeping my fingers crosse...any idea why this happened?