|Most likely an LCD screen problem. Connect an external monitor to the Laptop, if the Desktop displays properly the problem is with the LCD.|
Could be just loose connections between screen and Motherboard or you may need a new LCD.
Open Device Manager and see if any Display Adapter problems are indicated by either Yellow"?" or "!" .
Try removing the Display adapter in Device Manager, then reboot. This will reinstall Display drivers. If the LCD display is still corrupted , you probably need a new LCD.
Check with Packard Bell for any possible warranty you may have.
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