If your laptop screen is not displaying video properly, you need to run what is called the Built-in Self Test (BIST) to determine if there is a problem with the screen itself or some other issue that is preventing your LCD laptop from displaying an normal image. The BIST will help you isolate problems such as lines on the screen, fuzzy text and images or poor color resolution. This test is important, as it helps run diagnostics outside of the Operating System.If no video is being displayed on the screen, then you can try an external monitor to see if that works. This test, however, is to determine if there is a physical problem with the LCD screen or if this is a problem that can be corrected within software.
Run the BIST Test On Your Dell Laptop
To begin the BIST test, you should hold down the D key and press the power button. Release them both, and this should begin the BIST test. You should see two colored bars appear on the screen, then text asking if you saw them. Select NO to begin the test.
You will see several different screens displayed along with beeping and an error screen at the end. The error message is normal. During the test, you should be looking for the same symptoms you’re getting within Windows, such as lines on the LCD screen, poor color, etc.
If you do not see these problems, then the issue is likely with a bad Windows driver. You should visit the Dell support site and get the latest driver for your graphics card and update the system’s BIOS.
If you did see the same issues you experience within Windows, then you have a physical problem with the LCD screen and it will likely need to be replaced.
Read more of our Dell hardware troubleshooting articles.