Learning about sysprep is big topic - you need to research Windows Deployment Toolkit and Windows Automated Installation Kit. These are free tools.
So if it didn't work then there are other missing drivers.
You need to create a folder in say root of C:\Drivers and then place all the drivers you need for the new system in subfolders.
This is done while still in W7 on original machine.
Then you use pnputil -a C:\drivers\folderx\*.inf etc this "injects the drivers" into W7. This is tedious if you have many drivers to add.
Using a PowerShell script you can automate it to create bat. You then run bat file as Admin.
Open PowerShell and cd to C:\Drivers
New-Item -ItemType file C:\Drivers\DriverList.txt | Out-Null
get-childitem "C:\Drivers" -recurse | where {$_.extension -eq ".inf"} | foreach {
$CommandLine = "C:\Windows\System32\pnputil.exe -a " + """$_.FullName"""
Add-Content C:\Drivers\DriverList.txt $CommandLine
}
Add-Content C:\Drivers\DriverList.txt pause
Move-Item C:\Drivers\DriverList.txt C:\Drivers\DriverList.bat
Write-Host "Finished"