[SOLVED] --- Needed some compressed air allround and a piece of foil from atop the fan was loose inside the body, possibly ****ing something up or shorting something! Sorry for the massive noob timewasting here... Hey all, So I thought I had enough know-how from the old IFixIt website to open up my Macbook Core 2 Duo and clean out the fan, and try to remove the optical drive which no longer works. When putting everything back together, I get a completely black screen on power-up and no faint image or anything as far as I an tell, when titling the machine or otherwise. Normal fan/HDD/system sounds, everything boots but no display. Any suggestions as to where I might have gone wrong? Have tried reinstalling the optical drive and putting everything back exactly as it was but no luck. Some minor things that might have been altered: I tried blowing inside the machine a lot, around the logic board, fan and heat sink to remove dust, used a dry cotton cloth on a bit of it. I tried my best not to shift any of the black tape on the top of the fan/heat sink. One possibility is that the tape material on the end of the data display cable (the part which connects to the logic board) may have slipped a little bit? Tried moving it around but really it doesn't seem like anything has been torn. Pretty sure no pinching happened as the cables were totally freed up without the optical drive smooshing them against the fan. Already tried SMC and PRAM reset. Help! Thanks a lot. Mark edit: I should add that I also today took out one of the original 512mb ram cards and put in a 2GB, but everything worked fine on the first boot, and was recognised. No idea if that could affect things.