Need Help for not booting ACER 5100

Greetings from Turkey everybody.I need help . I closed lid of my laptop and it gone to hibernation mode. I told my brother to not unhook the charger, but he did and battery emptied itself. Now, even after its fully recharged, I cannot boot my laptop.When I press on button, the harddrive indicater is lit for some seconds, but theres not boot up screen or anything. Cpu fan keeps working, dvd drive works perfectly. I tried connecting it to a 17 crt monitor, still no results. Please help. Thank you.