You have the Pavilion already in your hands and you want to know if you add an RTX 2060, will the current 400w PSU be enough? No it wont. Most MFGs recommend a minimum 550w PSU for their 2060's.
I need the full Product number (not serial #) of your model to see what you have exactly.
Press Control/Alt/S for the information menu in windows Or Go to the Start menu and scroll to H/HP Help and Support/HP Support Assistant. Open the program and click on your computer in the list. The 7 digit Product Number will be listed in both those places.
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