Very good question! When shopping for a computer monitor, there are several key factors to consider:

1. Display size: Choosing the right size display can greatly improve your user experience. If you need something smaller, a 13- or 14-inch display is a good choice. If you need something bigger, you might consider an external monitor larger than 27 inches.

2. Resolution: The higher the resolution, the clearer the image. Generally speaking, 1080P resolution can already meet the needs of most users, but for designers, game enthusiasts, photographers and other professionals, 4K resolution will be more suitable.

3. Refresh rate: The higher the refresh rate, the smoother the picture. For players, the refresh rate must be at least 60Hz, and some monitors even support a refresh rate of 144Hz or even 240Hz.

4. Color performance: Color saturation, color accuracy and tone gradient are all important indicators to measure the color performance of the display. If you need to perform image processing or have other related needs, it is recommended to choose a display with a wider color gamut coverage.

5. Connection method: Consider the connection method supported by your computer, such as HDMI, VGA or DVI interface, etc. In addition, you can also choose a display with multiple interfaces for easier connection to other devices.

Hope this information helps you! If you have any further questions feel free to ask me.