HI shebaz;
Thank you for your inquiry. I am pleased to assist you!
I understand that your computer came with Windows 8, and you would like to downgrade it to Windows 7. I saw that this model can come with Windows 7,when I checked the specifications. Therefore we do have drivers listed. I would download the drivers to a USB. drive. Once you have accomplished that, boot to your windows 7 cd and install normally. Here is a Microsoft document on *How to perform a clean installation of Windows"click here. Once you have Windows 7 installed, then update the drivers from the USB drive. Then I would suggest you download the HP Support Assistant, and let it look for any errors or any more updates. HP Support Assistant click here. For your benefit I am also sending documentation on "Downloading or Updating Software and Drivers for HP Computers" click here. I hope this helps.