![](/images/new-backgrounds/1225240/225240173x1.webp)
Chapter 7: BIOS
Adjacent Cache Line Prefetch
The CPU fetches the cache line for 64 bytes if Disabled. The CPU fetches both cache lines for 128 bytes as comprised if Enabled.
I/O Device Configuration
Access the submenu to make changes to the following settings.
KBC Clock input
This setting allows you to set the clock frequency for the Keyboard Clock. The options are 8MHz, 12 MHz and 16MHz.
Onboard COM1
This setting allows you to assign control of Onboard COM1. The options are Enabled (user defined), Disabled, and Auto (BIOS- or OS- controlled).
Base I/O Address
Select the base I/O address for COM1. The options are 3F8/IRQ4, 2F8/ IRQ3, 3E8/IRQ4 and 2E8/IRQ3.
Onboard COM2
This setting allows you to assign control of Onboard COM2. The options are Enabled (user defined), Disabled, and Auto (BIOS- or OS- controlled).
Base I/O Address
Select the base I/O address for COM2. The options are 3F8/IRQ4, 2F8/ IRQ3, 3E8/IRQ4 and 2E8/IRQ3.