Same happened to me 2 months ago... Dv6000 are popular over heaters. Just one day it didn't turned on - only display light. But few days after that It worked when it had cooled down like 6 hours after every restart - LOL. In my case it was motherboard/heat sink wear off.
Hopefully your problem is not so great... go see technician or turn to warranty. I have heard they replace the motherboard if it happened inside warrant time.