Turn on the computer. Press and hold the Command (⌘) - Option - P - R keys before the gray screen appears. Hold the keys down until the computer restarts and you hear the startup sound for the second time. Release the keys.
Hold the left control and press the Alt option placed at your left, with a right shift key. Hold the above keys for at least 7-10 seconds. Without letting them release, press and hold the power button present on your MacBook Pro. Now, additionally, keep all these four keys pressed for about 7-10 seconds more.
Vertical lines on a PC screen may be a result of hardware failure, or a problem with your graphics card. If the lines are different colors, or with changes when you add pressure from the panel, then the issue is probably your PC's LCD screen.
How to Hard Reset MacBook, MacBook Air, or MacBook Pro
- To force a restart your MacBook, you need to press and hold down the Command (⌘) button, the Control (Ctrl) key, and the power button at the same time.
- Hold these keys down until your MacBook's screen goes blank and the computer restarts itself.
Shut down your Mac, then turn it on and immediately press and hold these four keys together: Option, Command, P, and R. Release the keys after about 20 seconds. This clears user settings from memory and restores certain security features that might have been altered.
Find the following keys on the keyboard: Command (⌘), Option, P and R. You will need to hold these keys at the same time in next step. Turn on computer. Hold Command (⌘)-Option-P-R before the gray screen appears.
Check the Cause of the Problem
- Restart your computer. Before the system starts booting, you'll see a screen.
- On the screen, you'll see which key you have to press to enter the BIOS, you usually have to press F10, Del, or F2.
- Once you enter BIOS, check if the red lines still appear.
1) Right-click on the empty area of your desktop and click Display settings. 2) In Resolution, click the drop-down menu and make sure the recommended resolution is selected. Then see if the horizontal lines disappear.
Right-click on the empty area of your desktop and click Display settings. In Resolution, click the drop-down menu and make sure the recommended resolution is selected. Then see if the vertical lines disappear.
A vertical line running down your computer monitor's screen usually is related to pixelation of the screen. Colors on the screen wear down over time and can actually dye and discolor the screens. The problem also can show up on flat-panel monitors that have been bumped.
Use a blunt-tipped object, such as a PDA stylus, wrapped in a soft cloth and apply gentle pressure for about 10 seconds to the stuck pixels. Remember where the problematic pixels are on your screen and turn the display off first. Turn your screen back on and look at them. Repeat if necessary.
5.Manually Fix Stuck Pixels
- Turn off your monitor.
- Get yourself a damp cloth so that you won't scratch the screen.
- Apply pressure to the area where the stuck pixel is.
- While applying pressure, turn on your computer and screen.
- Remove pressure, and the stuck pixel should be gone.
A dead pixel occurs when the transistor that powers it fails to supply power, causing it to remain permanently black, never illuminating. The most common cause of dead pixels is a manufacturing defect. Undetectably small errors in assembly can result in a handful of dead pixels among the millions of functional ones.
If you have 'video demo mode ' settings 'enable demo mode ' check marked with split screen mode as an option, you will see a red line. To remove it, simply uncheck 'enable demo mode ', press 'apply ' and then close with 'ok '.
Choose Apple menu > System Preferences, click Displays, then click Display. To see the Detect Displays button, press the Option key. Then click the button to detect the display. If the display is flickering: Make sure your Mac and display are connected to one another with good quality cables and adapters.
