There's a free online driver scanner here, but it downloads an ActiveX control in order to run (works with IE only, not Firefox or Opera) so you may not be too keen on that (only time I allow ActiveX code to run on my PC is from the Microsoft Update website 'cos it's the only way to get updates). Anyhow, it's here:
http://driveragent.com/
This one isn't free but you download and install it to use whenever you like, and it doesn't use ActiveX code. The trial is free but I guess there'll be some restriction on what it can do compared to the registered version.
give it a try before buying, it might just cover what you want.
http://www.drivershq.com/
Just a word of advice - don't assume that you 'must' have the latest drivers for the best performance. Very often a new driver will introduce fresh problems or 'bugs' you didn't have before, or give you worse results than the old driver. You should only update a driver if you know that the new one addresses a specific problem you're having. Otherwise leave the current driver intact. Remember "If it ain't broke, don't fix it".