I have an older Toshiba Satellite c655-s5049, after some research I decided to upgrade the CPU. I replaced the Celeron 900 with a Core 2 T7300. I also put a second 2gb ram stick in. I put the ram in, and everything worked fin, so I then put the CPU in. With the new CPU I get display when it is unplugged and running off of battery, but when I plug it in the display is so dark that I need a flash light to see it. I've checked the brightness settings in the power settings, and all appears well. I'm at a bit of a loss here.