if you bought the computer through a manufacturer, check the manufacturer's website under the downloads section. Alot of places have a driver search tool that allows you to look for the specific model of your machine and download the right drivers.
If you know the soundcard/video card make/model, I could help you find them.
should have drivers for you
To make sure drivers are properly uninstalled and updated properly, you should do the following:
1) download updated driver
2) uninstall old driver
3) reboot computer (to make sure all residual registry entries are removed)
4) install new driver
5) reboot computer
If you dont do it this way, you dont risk any damage, but improper driver installations can cause conflicts. This is the CLEANEST way to do it.