Why Does My Screen Jump Up & Down?Navigating long documents and Web pages requires the ability to scroll smoothly. Dealing with a monitor screen that jumps unexpectedly makes it difficult to read text and see Web pages properly. This jumpy behavior can occur due to numerous factors, ranging from software conflict or faulty hardware.
Malfunctioning Mouse
In some cases, a jumpy screen is caused by a malfunctioning mouse. Many computer mice offer a scroll wheel in between the two selection buttons on the front, which helps scroll without the use of the scroll bar on the right of the screen. A faulty mouse may send incorrect commands to the computer, resulting in a jumpy screen. Try a different mouse on your computer to see if the screen continues to jump. If not, the original mouse was your culprit.
Outdated Drivers All the components within your computer require specialized files called drivers to communicate with each other properly. A jumpy screen could indicate out-of-date drivers in the graphics card or monitor. If these files are older, they may not work properly with each other or the operating system, causing odd screen behavior. Updates for your operating system are found at Microsoft.com, while your computer manufacturer's support Web pages may offer driver updates specific to your system.
Monitor Issues
Monitor failure produces odd screen behavior, including flickering, jumping and color changes. Older, large CRT monitors contain components inside that degrade over time, and are susceptible to magnetic interference, both of which can produce a jumpy screen image. Failing monitors do not communicate with the computer and graphics card properly, regardless of driver version. Connect your jumpy monitor to another computer and see if the problem persists. If it does, it's a good indication that the monitor itself is at fault and needs replaced.
Virus Infestation Even if you have the most up-to-date drivers and operating system, a virus infestation can cause any number of problems within your computer and display. A virus can alter the way your monitor communicates with the mouse, graphics card or motherboard, which can in turn cause screen issues such as jumping. Run a virus scan to find and remove any hidden invaders that may be causing your screen issues.
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