Laptop black screen with cursor

Hello,

sir basically my lap is windows7 for the requirement of software work i changes into windows8.1 after installation it's work properly for two days,after that i install chrome,antivirus,bluestacks apps from then iget a problem in my laptop that is when we start the lap the screen was black with cursor,after that with some it officials advice i reinstall the os8.1 again i get same problem is there any lap problem please help me and the duration of buy's laptop is 6 months