Dell N4010 power problem.

I'm living in Cambodia. I have a problem with my Dell Inspiron N4010 Core i3.
My problem is that :
 
1. When I turn on the laptop, I need to wait 30 second to see dell start screen appears (not windows startup problem) then it starts the OS fine.
2. I can't turn off the pc by windows. When windows is off already, the machine doesn't go off. The screen becomes blank but the LED light still remains. All I have to do is hold on the power button to off.
3. I can't go to sleep mood. Whenever I put to sleep, the windows goes off and the machine still on.
4. I can't restart. When I restart the windows goes and the machine also go off but it take almost a minute to off after windows is off.
 
I am sure that it is not the software problem. I tried to set up windows again already. I also tried to flash BIOS update provided by dell website ( from BISO version A10 to A13) but still have the same problem.

 I dropped it once, but after that it was working fine. A week later I left it on until the battery is empty when I charge the battery again and turn the pc on I have this problems. I tried removing the battery already but still.
 
Please Kindly reply and help me. I need your ideas. The technicians in my country have no ideas to fix this. I hope you will be kind and help me.