Trying to fix son's dell inspiron 5100 laptap that he uses for school, it runs windows XP home and was purschased used a couple of years ago. The computer works fine if hooked up to monitor, but the laptop screen will only show white. You can control the brightness of the white. the computer has alway ran hot and have found the heat sink to be blocked with lint while trying to fix screen issues. I do not know a lot about laptop repairs and the computer is not worth a lot of money, but we need it running for school work. Any help would be great.