OK, hang in there,
The technician said something wrong with BGA Component and replaced it.
Is this were the
VGA cable is plugged in the screen goes blank
If your technician replaced the BGA, then take it back, as he didn't fix it. Also, make certain your technician has a HIGH-RELIABILITY station he is working on. I am certain he will show you the impressive work bench that he is working with! Then ask him to show you the TESTING and PMEL unit he is working with....as once again, he would have some precision measurement devices he would be proud of!
This is what is should look like; https://www.youtube.com/watch?v=PgncMQJZyxg
Then, after all of that, the display can still be jacked! Look athe last second of the screen as posted. It is jacked up, with a black line going throuhg the BIOS screen, and that wasn't a VIDEO artifact!
PLEASE NOTE!!! THE LINK TO THE VIDEO WILL BE TAKEN DOWN WITHIN 3 DAYS. THE VIDEO WAS AN EXAMPLE OF WHAT CAN HAPPEN, EVEN THOUGH YOU HAVE A GOOD RIG.!!!!