Like everyone else, i opened it to clean out the fans. Took off covers, keyboard, mem cards x 4,, 2 top and 2 bottom. Put it back together , hit the button. It turns green and for a fraction of a second, the fans bump,, then nothing but a green light. No beeps no error message, in fact the screen doesnt have a chance to come on, its still short about 2 seconds before it woul kick on. All i can think is either the cards arent in the correct spots so it cant find the boot, if it works like that idk, or maybe not having a long enough screw in the right spot so it isnt grounding right. And i dont know if they work like that either.