Horizontal lines show up

I have installed linux mint 64 bit on my lenova government laptop.it had worked well initially, all of the sudden it shows up horizontal lines on screen after the password process finished which means once the screen get into the home page the horizontal lines showed up all over my screen, It throws a error page before starting… I think i am stucking in this place. I need support to get over this issue. Thanks for your time. I will attach the image which shows error in the beginning.

Did you tried forceshutdown your pc and reboot the system check if the problem persists .