Answer:
When you shut down your PC, all your open programs close and the PC shuts down your operating system. but In sleep mode, the PC enters a low-power state. The PC's state is kept in memory, but other parts of the PC are shut down and won't use any power.
Explanation:
If your computer is old it may be the screen is dying or if its brand new it would probably be the power supply check your battery or cables
