Asus M2N DH - Manual (Page 80)

4-20 Chapter 4: BIOS setup
The following items appear only when the AI overclocking item is set to
[Manual].
CPU Frequency [200]
Displays the frequency sent by the clock generator to the system bus and PCI bus.
The value of this item is auto-detected by the BIOS. Use the <+> and <-> keys to
adjust the CPU frequency. You can also type the desired CPU frequency using the
numeric keypad. The values range from 200 to 300.
PCI Express Frequency [Auto]
Allows you to select PCI Express frequency.
Configuration options: [Auto] [100] [101] [102]... [150]