Why my laptop won't turn on?

Asus X551M Laptop

Hey guys, today I have loft my laptop for about half an hour working, when i came back the screen was black, yet i could hear the music. I tried pressing power button long enough to turn it off, and once it did i tried booting up. The problem is it won't turn on anymore, no fan noise, no lights turning green, just no respond from the device. I've tried taking off the battery, booting w/o it, still no clue. The motherboard seems OK tho. Any ideas on how to get it back working?