If you think the power plug is not working properly, plug it into different outlets. Also, this might be the case when there is no power supply in your laptop from the AC adapter and thus the device is failing to boot properly. This is the condition when the major components of your laptop are not working properly. If your Asus laptop is getting the black screen display now and then or it is just stuck on it, then you can consider the following suggestions.
Part 1: How to Solve the Asus Laptop Black Screen Problem?