My MacBook pro won't start up. When I press the power button I the screen does not come on. I hear the disc drive, the hard drive, and the fans. the hard drive stops seeking almost imediately but continues to run. The power indicator lights up brightly and then dims. If I close the lid the light brightens, and if I open it it dims again. There is no sound if I press the volume buttons. I have tried plugging it into another screen, resetting the smc, resetting the pram, starting up in target disc mode, and even removing the hard drive and erasing the sleepimage file from a friends mac. Does anybody have any suggestions? Update: I am able to use my hard drive on his mac, so that is not the problem.