For the drivers and BIOS files go to
this area. Then click on either BIOS or Drivers in the upper left corner. After it goes to that page select/click the K7S5A and you should find what you need. Do not use the "drop-down arrow in the window at the middle top of the page as this will further confuse you. Just find the "K7S5A" and click on it when you get to the BIOS or Driver page.
There will be a version of all of the above files on the installation CD. It is best to use that to start with as it has an automated driver loading program that works well with very little work on your part besides patience. Then, make sure the system is up and running well for a period of time before you decide to update any of the files or the BIOS. You should have no problems then.