Ok so my brother has an apple powerbook G4 laptop. heres the problem: You can turn on the laptop and hear it running, the numlock key, caps lock key, and scroll lock keys all light up after you turn the laptop on. you can even change the volume and hear it make the click sounds, so the screan just wont light up. I think it is a GPU problem because i have tried plunging in my monitor into the DVI connection on the side of the laptop which i have used before with a monitor and it had worked, but this time it didnt, so Is the GPU dead? IF so What GPU should i get costing under $100 or so?