LCD BLACK SCREEN EVEN ON EXT. MONITOR

i recently put my laptop to hibernate and when i tried turning it on it powered on but the screen would not light up, also hard drive LED is not lit up, i hear some components start up, though it might just be the fan and CD drive, it charges fine, it's never done that before, i hibernated the day before and it took a while to load and eventually loaded, the next day i was working on it and hibernated it several times because of the low battery, and my charger stops charging if it overheats i guess, so i let it cool off for a while and then charged it up for a bit, i did this 3 times, and then the 4th time i tried booting it wouldn't. if anyone could help me that'd be great, i've tried taking out the battery and holding the button for 30 secs, tried that with the AC and the battery out, tried external monitor but gives no output. im thinking some connectors may be loose, or something overheated, ive also read that the RAM could be the culprit. please help. thanks!