A:Answer Hello John,
We're sorry that there's an issue with overheating on your new Surface Laptop 3. First, we recommend making sure that its software and firmware has been updated to the most recent versions. If that doesn't help, please run the Surface Diagnostic Toolkit. For more information, go here: https://support.microsoft.com/en-us/help/4037239/surface-fix-common-surface-problems-using-surface-diagnostic-toolkit
If all else fails, please reach out to Microsoft Support for assistance here: https://support.microsoft.com/en-us/contactus/
Hope that helps,
Chuck
Surface Customer Care