I have a white Macbook that is 2 years old and I just took it on a trip but it wouldn't turn on. I had forgotten my charger and figured it was just out of battery. I open it up, press the power button, then it makes the chiming sound but the screen stays dark. The little light that comes on when the computer is on comes on briefly, only to turn right off again. Then it looks like I have the brightness way down low because at the right angle you can sort of see the login page, but when I try to turn the brightness up nothing happens. I tried pressing enter and then putting in my password, then the screen went totally black. I've had it plugged in all day and I have removed the battery and replaced it. I've also tried resetting the SMU or whatever it's called like people suggested on other forums. Nothing. Any ideas?