I've run into a very nasty problem with my macbook (late 2007 normal macbook model I think). Whenever it closes, the monitor goes black. This is normal. What isn't normal is this: whenever I open it and then either start it/awaken it, it gives me the screen... and then the monitor turns the brightness off again! This happens randomly, I have to close and open my screen quite a few times to get it to work-even if I restart the computer. I don't what's causing this, or how to fix it, although I have a hunch that it's the hinge on the back; it started shortly (but not directly) after I replaced my CD drive... I have the tools and instructions needed to open my machine up if it's a fairly simple fix, but I need to know what's going on first. Please help? I have already tried resetting the SMC.