Asus P5B - Manual (Page 81)

ASUS P5B 4-7
4.4 Advanced menu
The Advanced menu items allow you to change the settings for the CPU and other
system devices.
Take caution when changing the settings of the Advanced menu items. Incorrect
field values can cause the system to malfunction.
Jumperfree Configuration
USB Configuration
CPU Configuration
Chipset
Onboard Devices Configuration
PCIPnP
4.4.1 Jumperfree Configuration
Configure System Frequency/Voltage
AI Tuning [Auto]
AI Tuning [Auto]
Allows selection of CPU frequency and auto adjustment of relevant parameters.
Frequencies higher than CPU manufacturer recommends are not guaranteed to
be stable. If the system becomes unstable, return to the default. Configuration
options: [Manual] [Auto] [Standard] [AI N.O.S.]
DRAM Frequency [Auto]
Allows you to set the DDR operating frequency.
Configuration options: [Auto] [DDR2‑533MHz] [DDR2‑667MHz] [DDR2‑800MHz]
Selecting a very high DRAM frequency may cause the system to become
unstable! If this happens, revert to the default setting.