If you haven't done so yet, install the latest Chipset and Video drivers from your Dell Product Support page. Just click on your Dell model number in the link below. In your Dell Product Support page, select windows 11 and then Check for Updates.
After installing latest Dell drivers onto computer, make sure computer has latest windows 11 updates from Microsoft.
Update Windows (microsoft.com)
Please click on link below for additional information that might be helpful to you:
How to Troubleshoot Display or Video Issues on a Dell Laptop | Dell US
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