A secure motherboard for a computer, wherein each user accessible peripheral port is protected by hardware based peripheral protection circuitry soldered to the motherboard. The protection circuitry provides security functions decreasing the vulnerability of the computer to data theft. User input ports such as keyboard and mouse peripheral ports are coupled to the computer through a security function that enforce unidirectional data flow only from the user input devices to the computer. Display port uses a security function which isolates the EDID in the display from the computer. Authentication device such as smart card reader is coupled to the computer via a port having a security function which enumerates the authentication device before coupling it to the computer.