With a Dell computer you have but to go to the Dell support site and enter in your express service code and that will bring up your computer and all it's spec's. You can also check out if your computer is capable of the Windows 8 upgrade and see what parts you have that require drivers, Windows 8 will have some selection of drivers with it and if you need others you can go to the manufacturers support web page to see if they have Windows 8 drivers.
Upgrading to Windows 8 will require new drivers for your components. Dell will have some and what they don't have you may have to search for at the support sites of those parts.