Here are some troubleshooting steps that may help in isolating the problem.
- Start with a hard reboot, remove the battery and unplug it's AC adapter then press and hold the power button for 20 seconds then try booting it.
- If it doesn't work reseat the RAM, remove them all for couple of second then put them back in making sure everything is seated properly.
- Next to try is if your AC adapter is still okay by trying another AC adapter that has the same voltage and see if it would work.
- If all these will not work it would be a motherboard problem.
- If it's still under the factory warranty I would suggest contacting ASUS for a repair.