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If a vertical dark shadow or line appears on a new monitor, first check whether it also appears over the monitor’s own on-screen display (OSD) menu or its no-signal screen. If it does, manufacturer troubleshooting guidance points to a monitor-side problem; if those screens are clean, investigate the cable and connected device first.
Check whether the line appears on the monitor’s own display
Open the OSD using the monitor’s physical buttons or joystick. The OSD is generated by the monitor, not the computer, so a line that runs across the menu is a useful clue. ViewSonic calls opening the OSD the quickest way to isolate the cause in its monitor line troubleshooting guidance.
For a second check, leave the monitor powered on and disconnect its video cable. Look at the resulting no-signal or cable-not-connected screen. Acer and LG also recommend this kind of self-test in their guidance for Acer monitors and LG monitors.
| What you see | What it suggests | What to do next |
|---|---|---|
| The line overlays the OSD or remains on the no-signal screen | A monitor-side issue is more likely under these manufacturer tests. | Contact the seller or manufacturer for support and check whether an exchange or return is available. |
| The OSD and no-signal screen are clean, but the line appears with your usual source | The cable, computer or other source device, graphics hardware, or software path may be involved. | Reseat or substitute the cable, then test another source device if available. |
| The symptom changes when you swap cables or source devices | A signal-path component or source may be contributing. | Change one item at a time to identify which swap changes the symptom. |
These observations help isolate the problem; they do not identify a specific failed component or guarantee a diagnosis.
#1 Best Overall
- CRISP CLARITY: This 23.8″ Philips V line monitor delivers crisp Full HD 1920x1080 visuals. Enjoy movies, shows and videos with remarkable detail
- INCREDIBLE CONTRAST: The VA panel produces brighter whites and deeper blacks. You get true-to-life images and more gradients with 16.7 million colors
- THE PERFECT VIEW: The 178/178 degree extra wide viewing angle prevents the shifting of colors when viewed from an offset angle, so you always get consistent colors
- WORK SEAMLESSLY: This sleek monitor is virtually bezel-free on three sides, so the screen looks even bigger for the viewer. This minimalistic design also allows for seamless multi-monitor setups that enhance your workflow and boost productivity
- A BETTER READING EXPERIENCE: For busy office workers, EasyRead mode provides a more paper-like experience for when viewing lengthy documents
If the monitor-generated screens are clean, check the signal path
- Reseat the video cable. Disconnect and reconnect it securely at both the monitor and source-device ends.
- Try a known-working compatible cable. Match it to the ports and display requirements of both devices. Identify whether your setup uses HDMI, DisplayPort, USB-C, or another connection before substituting a cable. ViewSonic and ASUS monitor troubleshooting guidance both include trying a suitable working cable.
- Connect another source device, if possible. If the line appears only with the original computer or device, that narrows the issue toward its connection, graphics hardware, or software rather than the monitor alone.
- Reset the monitor’s settings. If the monitor-generated screens are clean and the problem persists, use the OSD’s reset option. ViewSonic refers to this as Memory Recall or All Reset; menu wording varies by model.
- Check the computer’s software or graphics driver. Acer includes software and driver checks among possible troubleshooting paths when its self-test does not point to the monitor hardware.
If the line remains on the OSD or no-signal screen
Contact the monitor manufacturer or seller rather than trying to diagnose a particular panel, board, or pixel fault from the appearance alone. Have the model and serial number ready, along with the purchase date. A photo or short video showing the line on the OSD or disconnected-screen display can help explain the symptom.
Because the monitor is new, check the seller’s return or exchange process promptly. Eligibility and timing depend on the seller, location, and purchase details; no specific deadline or entitlement applies universally. Warranty coverage and any pixel policy also depend on the product and seller or manufacturer terms.
Quick Recap
Best Value
- 【INTEGRATED SPEAKERS】Whether you're at work or in the midst of an intense gaming session, our built-in speakers provide rich and seamless audio, all while keeping your desk clutter-free.
- 【EASY ON THE EYES】 Protect your eyes and enhance your comfort with Blue-Light Shift technology. This feature reduces harmful blue light emissions from your screen, helping to alleviate eye strain during long hours of use and promoting healthier viewing habits.
- 【WIDEN YOUR PERSPECTIVE】Our sleek minimal bezel design ensures undivided attention. The nearly bezel-free display seamlessly connects in a dual monitor arrangement, delivering an unobstructed view that lets you focus on more at once, completely distraction-free.
Rank #4
- CURVED FOR ENHANCED ENGAGEMENT: An immersive viewing experience with a curved monitor that wraps more closely around your field of vision; It creates a wider view, enhancing depth perception and minimizing peripheral distraction
- SMOOTH PERFORMANCE FOR SEAMLESS CONTENT: Stay in the action when playing games, watching videos, or working on creative projects; The 100Hz refresh rate reduces lag and motion blur so you don't miss a thing in fast-paced moments¹
- MORE GAMING POWER: Gain the edge with optimizable game settings; Color and image contrast can be adjusted to see scenes more vividly and spot enemies hiding in the dark; Game Mode adjusts any game to fill the screen so you can view every detail²
- KEEP IT EASY ON THE EYES: Care for your eyes and stay comfortable, even during long sessions; Advanced eye comfort technology certified by TÜV reduces eye strain by minimizing blue light and reducing irritating screen flicker²
- INCREASED VERSATILITY: Connect to more; Plug devices straight into your monitor for increased flexibility, making your computing environment even more convenient
Rank #3
- Clear visuals. Fluid motion: A 144Hz refresh rate and 1ms MPRT deliver smooth, tear‑free motion across work, gaming, and streaming for clearer, more fluid viewing.
- Eye comfort: TÜV Rheinland 3‑star* certification reduces harmful blue light while preserving stunning color quality without compromise. *TÜV Rheinland 3-star eye comfort certification.
- Wide viewing angle: Get consistent views across a wide 178° /178° viewing angle.
- In-Plane Switching (IPS): See excellent color accuracy and consistency across wide viewing angles with In-plane Switching (IPS) technology.
- Ultra-thin bezels: Maximize your viewing experience with thin bezels.
Rank #2
- CRISP CLARITY: This 22 inch class (21.5″ viewable) Philips V line monitor delivers crisp Full HD 1920x1080 visuals. Enjoy movies, shows and videos with remarkable detail
- 100HZ FAST REFRESH RATE: 100Hz brings your favorite movies and video games to life. Stream, binge, and play effortlessly
- SMOOTH ACTION WITH ADAPTIVE-SYNC: Adaptive-Sync technology ensures fluid action sequences and rapid response time. Every frame will be rendered smoothly with crystal clarity and without stutter
- INCREDIBLE CONTRAST: The VA panel produces brighter whites and deeper blacks. You get true-to-life images and more gradients with 16.7 million colors
- THE PERFECT VIEW: The 178/178 degree extra wide viewing angle prevents the shifting of colors when viewed from an offset angle, so you always get consistent colors
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