After turning on I don't see the POST. The screen stays black and the only sound I hear is ventilator noise. The small display just near the main switch with dvd-rom symbol on it lights red. I've pull out the dvd-rom module, replaced the hard drive, battery module and memory plate one after one (I have two of them) - the same result. What can be wrong? One my assumption is the laptop power connector. The central rod in it became loose. I could check it but not sure how to get inside. Can anybody give me a hint? Another assumption is cpu. The only thing I know about it that it's Intel Centrino because of the sticker on the dashboard. Can anybody give me more information about it? To check or replace cpu I also need to know how to open my laptop.