Help! display messed up after applied thermal paste

[razeredge7]

So, I asked a local technician to apply thermal paste because my laptop became way too hot when playing games.
But after applying the thermal paste, the screen became like this.
http://imgur.com/a/lh7IW

well......what happened to my laptop..?
I argued with the local technician for destroying my laptop.
Please help. it contains important data

 

[bootcher]

Your local 'technician' probably is an amateur. To me it looks like the cable connecting the screen isn't properly connected, or the cable has been broken. In any case he should've noticed something wrong with your screen after applying the paste and putting the laptop back together. I would demand he fix it. If not I would go to the police.
Your data is on the laptop harddrive which can be removed, and should be safe.

 

[razeredge7]

well, the BIOS screen does not flicker. The flickering issue starts AFTER the booting process completes.
changing the display to Intel graphic still the same, flickering issue...

 

[bootcher]

It could be, BIOS uses other resolution than windows.

 

[razeredge7]

so..the main problem is the cable..?