I have a Dell D800, 1.8 ghz processor, 1.5 gig ram, 40 gig hard drive. WinXP SP2 After pressing the power button, all the lights stay on for about 3 seconds then turn off. I have removed the battery, hard drive,RAM, and disconnected the LCD monitor, video card and processor as well as where the power/reset panel button is connected. Then i put it all back together. Same result. However it doesn't do anything (no lights) when i disconnect the AC power plug in. (running on battery only) The only thing i did not disconnect was the keyboard. Any help or suggestions are greatly appreciated. Thanks