K7n2 is the type of the motherboard
That looks like a model number. Is the name of the vendor somewhere on the surface of the motherboard (Gigabyte, ASUS, Biostar, MSI, etc)?
Likely, it is a MSI motherboard. Check this link:http://www.msi.com/product/mb/K7N2.html
All available downloads, including the BIOS, can be found here. Good luck!