Asus P5B CPU Frequency, Dram Frequency Auto, PCI Express Frequency Auto, Spread Spectrum Auto

The following items appear only when you set the AI Tuning item to [Manual].

CPU Frequency [XXX]

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 100 to 400. Refer to the table below for the correct Front Side Bus and CPU External Frequency settings.

FSB/CPU External Frequency Synchronization

Front Side Bus	CPU External Frequency
FSB 1066	 MHz
FSB 800	00 MHz

DRAM Frequency [Auto]

Allows you to set the DDR operating frequency.

Configuration options:

Available DRAM frequency options in various FSB settings

FSB				Configuration options
	Auto	DDR2-	DDR2-	DDR2-	DDR2-	DDR2-
				00	889*	1067*
FSB 1066	•	•	•	•	•	•
FSB 800	•	•	•	•

* Provided for overclocking purpose only.

Selecting a very high DRAM frequency may cause the system to become unstable! If this happens, revert to the default setting.

The DRAM Frequency item also appears when you set the AI Tuning item to [AI NOS].

PCI Express Frequency [Auto]

Allows you to set the PCI Express frequency. This item is set to [Auto] by default. Configuration options: [Auto] [90] [91] ~ [149] [150]

PCI Clock Synchronization Mode [Auto]

Allows you to synchronize the PCI frequency with the PCI Express or CPU frequency. Configuration options: [Auto] [33.33MHz]

Spread Spectrum [Auto]

Allows you to enable or disable the clock generator spread spectrum. Configuration options: [Disabled] [Enabled] [Auto]

ASUS P5B Deluxe 4-17