Black screen on boot - dual screen active - Need Solution

I have been facing major problems and need a solution 

Steps to recreate the problem, 

1. Boot my Laptop - Main screen dark 
2. I am able to listen to coot completion sound 
3. Plugin my dual screen from HDMI port - i see the login screen shifted to my dual screen
4. Remove the HDMI cable - main laptop screen dark 

Dell service center of no help - they took money from  me but of no help

Procedure to bring display back to the main laptop screen 

1. Boot my Laptop - black screen 
2. Hold the power button for more than 30 seconds and the laptop keyboard display goes dark (assume laptop shutdown or some sort of reset) 
3. Repeat the #1 and #2 multiple times 
4. Then the main display comes back 

From there on it works perfectly

Power Management 

All set to never - 

Earlier, if i had kept the laptop idle for 5 mins or more, and the display was switched off by power management settings, the main display never came back and the only the dual screen was active 

I have been facing this problem for sometime now and need some sort of solution on it.