Agree with Tmagic650. Could be a bad hard drive, bad memory module, bad cmos battery, bad power switch, bad ribbon cable from system board to LCD screen, or water arrived onto the system board through the keyboard... and sometimes electronics components go bad just as a light bulb reaches the end of its useful product life. But if Tmagic650's idea doesn't work, you may need the assistance of somebody with test instruments... if a change out of hard drive or memory do not work.