Asus P8Z77-V PRO/THUNDERBOLT - Manual (Page 108)

3-32 Chapter 3: BIOS setup
Chapter 3
Serial Port Configuration
The sub-item in this menu allow you to set the serial port configuration.
This item functions only if there is a serial port (COM1) connector on the motherboard.
Serial Port [Enabled]
Allows you to enable or disable the serial port (COM).
Configuration options: [Enabled][Disabled]
Change Settings [ IO=3F8h; IRQ=4 ]
Allows you to select the Serial Port base address.
Configuration options: [IO=3F8h; IRQ=4][IO=2F8h; IRQ=3][IO=3E8h; IRQ=4][IO=2E8h;
IRQ=3]