BIOS is part of the motherboard, it is one of the chips onboard. No drivers needed, only thing you can do is update it, via the instructions, etc. from the manufactures website.
BIOS is for setting up the hardware INTO the motherboard: hard drives and their settings, boot order, CPU settings, Memory settings, port settings, and whether or not onboard or added cards are used.
Drivers are for the Operating System. The more resent the OS, the more "modern" drivers it will have.
Of course, manufactures do update their drivers, and most of the time, Windows Update can get them, if provided to Microsoft. Which most do. Some don't, they just get you up and running.
If you have a devices manufactured AFTER the release of the OS, you'll need drivers.
If the device is onboard, the manufactures would have provided a "Driver CD" for installation of the drivers needed after/during OS install.
If the device is added on, the manufacture would have provided a "Driver CD" for installation of the driver before/after installing said device.
You can always download drivers from each manufactures website.
P.S. Always check compatibilty with current hardware to a new/different OS!! The OS will have tools/websites to do that. MANY people install Windows 7 without checking to see if their hardware is compliant, only to find out that Windows 7 doesn't support something (i.e. Sound Card).