ECS 649-M2, Manual, Page: 51 / 98

45
Using BIOS
Frequency/Voltage Control
This item enables you to set the clock speed and system bus for your system. The clock
speed and system bus are determined by the kind of processor you have installed in your
system.
CPU Clock Ratio [ 0 X]
Auto Detect PCI Clk [Enabled]
Spread Spectrum [Enabled]
Colck Control By [Auto]
Async PCI Clock control Disabled
CPU Clock 100
CPU:DRAM Frequency Ratio SPD
DRAM Frequency
Item Help
Menu Level
Phoenix-AwardBIOS CMOS Setup Utility
Frequency/Voltage Control
F5:Previous Values F6:Fail-Safe Defaults F7:Optimized Defaults
: Move Enter: Select +/-/PU/PD:Value F10:Save ESC:Exit F1: General Help
CPU Clock Ratio (0 X)
Use the CPU Host/SDRAM/PCI Clock to set the frontside bus frequency for the installed
processor (usually 133 MHz, 100 MHz or 66 MHz). Then use
CPU Clock Ratio Jumpless to
set a multiple. The multiple times the frontside bus must equal the core speed of the installed
processor e.g.,
3.5 (multiple) x 100 MHz (frontside bus) = 350 MHz (installed
processor clock speed) .
Auto Detect DIMM/PCI Clk (Enabled)
When this item is enabled, BIOS will disable the clock signal of free DIMM/PCI slots.
Spread Spectrum (Enabled)
If you enable spread spectrum, it can significantly reduce the EMI (Electro-Magnetic
Interference) generated by the system.
Clock Control By (Auto)
Use this item to set the CPU Host Clock frequency to Auto or by manual setting. Select
“Manual” to activate the following items and set each item manually.
• Async PCI Clock control (Disabled) : This item allows you to select the
fixed clock to generate the output to PCI frequency.
• CPU Clock (100) : Use the CPU Host Clock to set the fronside bus frequency
for the installed processor (usually 200MHz, 133 MHz or 100 MHz).
• CPU:DRAM Frequency Ratio (SPD): This item determines if the DRAM fre-
quency is controlled by SPD or by manually. Do not change the value in this
field unless you know the specification of the installed DRAM orthe installed
CPU quite well.
x
x
x
DRAM Frequency
Use this item to set the frequency of the installed DRAM. We strongly recommend users
leave this item at its default value. Inappropriate value may cause the system to be unbootable
or crash.