Here are the specs for your HP Pavilion dv9815nr Entertainment Notebook Computer. According to the specs, this model shipped from the factory with Windows Vista 32-bit installed. The HP Pavilion dv9815nr Entertainment Notebook PC Drivers & Downloads page for your computer only lists Windows Vista drivers. HP doesn't provide drivers for Windows 7 nor will it support the installation of Windows 7 on this model.
Please see "General Windows 7 Upgrade Guide for HP Laptops" by CherylG and Rakhmad Siregar for helpful information on finding Windows 7 compatible drivers or workarounds to make your computer fully functional. Please pay attention to "Level 2" and "Level 3" intructions, as that is were your computer falls.
FYI... I had two HP Pavilion dv9617nr Notebook Computers that are almost identical to your HP dv9815nr. I upgraded to Windows 7 64-bit almost immediately and found all the software and drivers to make them fully functional. About two years ago, I sold them for $300 each. When I sold them, I did a clean install of Windows 7 32-bit with all the lastest drivers I could find. Heck, one of them I did from 1200 miles away... teleconferenced with the wife and had her do everything remotely. I may be able to locate the drivers I used, if you would like.
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