Black screen issue with Laptop

Hello there! I am hoping one of you friendly folks might be able to assist me with a bit of an issue I am encountering with my Lenovo B560 laptop.

The current issue the system is having is when it is turned on the system's screen will remain black as if the system were off, although the systems LED lights do turn on and I can hear the HDD on the system which would indicate to me that the system is on with no display.

So far these are the steps I have taken to try and address the issue:

1. Thoroughly cleaned all of the dust out of the laptop to ensure it is not over heating.

2. I have power cycled the device by removing the battery from the laptop and unplugging the device from its power adapter, then holding down the power button for 60 seconds, plugging the laptop back into with the adapter, and tried once more with no luck. I have done this with and with out the battery to see if it made any sort of difference, which I did not. The battery LED on the system does indicate if the battery is attached, however, so I am unsure if the issue would be related to it. I have repeated this step numerous times.

3. I have attached the system to an external monitor and tried booting the system with it connected. When doing so the monitor will recognize that the system is attached to it by displaying the amber led light where the power button is located. Upon turning the system on no display appears on the monitor to indicate that the system is POSTing.

4. I have swapped out the RAM on the system with no results.

I should mention that prior to this issue the laptop was having a problem where it would shut it self off after about 5 minutes of use, which would lead me to believe that the issue is related to the way in which the system gets power.

Any assistance with this issue would be greatly appreciated!