Sony Vaio PCG-7F1L laptop won't start

[jlambe5]

I have a Sony Vaio PCG-7F1L laptop and I can't get it to start. I was having trouble with it shutting off if I opened the screen greater than about 20deg. I think I solved this problem. I unplugged every cable in side and reseated them. Some of them seemed rather loose or just not pushed in all the way. I also disconnected everything I could inside and reconnected. That seemed to solve the problem. It worked fine for a week or so. THEN, my wife was using the laptop and it just shut off for no reason. Off, blank, dead, nothing etc. Now I can't get it to come back on. With just the battery, no AC adapter - absolutely nothing, no lights, no noises. With the battery & AC adapter, the battery light on the front panel will flash green. 2 quick flashes and a pause, 2 quick flashes and a pause, etc. Which I assume is the battery charging. I've tried it without the battery and only the AC adapter, absolutely nothing. At the advice of a local computer tech, I've removed both the battery and AC adapter, held the power button for +30sec then put them both back and still nothing. Any ideas what could be causing this? I'm afraid it's going to be the mobo.