Step 2: List Components, Get Drivers
You've contacted your PC maker for a Windows 7 installation disc or list of components specific to your machine and come up empty. The next step is to create one. This needs to happen before the Win8 bits are wiped from the target system.
Open the Device Manager by pressing the Windows and X keys together and selecting Device Manager from the list. Expand each device until there's a list of all the components. Unfortunately, Windows offers no command for directly printing from Device Manager, so you'll have to write them down or print screenshots. Be sure to note manufacturer and model numbers for the three most critical components: display adapter, network adapter and pointing device (if other than an ordinary mouse).
Visit the support pages for each component and download drivers for the desired OS and store them on a USB drive or CD. Do not burn them to the Windows 7 CD and do not leave them on the system hard drive.