> For the complete documentation index, see [llms.txt](https://docs.sevenpens.com/drawtab/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.sevenpens.com/drawtab/troubleshoot/tsg-display-black-bars.md).

# TSG: Black bars on a display

## Overview

When using a pen display or a monitor you may experience black bars on the display. They may appear on the sides, on the top & bottom, or on all sides.

<figure><img src="/files/xPPra0Iqw5yPm5ZFl97V" alt=""><figcaption></figcaption></figure>

## Causes

**Incorrect resolution send to the display**

If there is a mismatch in the resolution your computer sends the to the display and the native resolution of the display, bars can appear. This is especially likely if the aspect ratios differ. For example: if your monitor is 1920x1080 but it receives a 1920x1200 signal you will get vertical black bars on the side.

**Duplicated/Mirrored displays**

If you are mirroring two displays, and they have different resolutions, black bars is very common result.&#x20;

## Things to try

* Verify the resolution being used for the video signal being sent to the display
* Disable display duplication/mirroring
* Try a different video port&#x20;

## Links

* [Mirroring or extending](/drawtab/guides/customizing/mirroring-or-extending.md)