GIGABYTE GA-8I845GVM775 - Manual (Page 39)

BIOS Setup - 39 -
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CPU Host Clock Control
Note: If system hangs up before enter CMOS setup utility, wait for 20 sec for times out reboot.
When time out occur, system will reset and run at CPU default Host clock at next boot.
Disabled Disable CPU Host Clock Control. (Default value)
Enabled Enable CPU Host Clock Control.
CPU Host Frequency (MHz)
100MHz ~ 355MHz Set CPU Host Clock from 100MHz to 355MHz.
Incorrect using it may cause your system broken. For power End-User use only!
Fixed PCI/AGP Frequency(Mhz)
Fixed PCI/AGP frequency.
Host/DRAM Clock Ratio
(Warning: wrong frequency may make system can’t boot, clear CMOS to overcome wrong
frequency issue)
2.0 Memory Frequency = Host clock X 2.0.
2.5 Memory Frequency = Host clock X 2.5.
Auto Set Memory frequency by DRAM SPD data. (Default value)
Memory Frequency (Mhz)
The values depend on "Memory Frequency For" item.
PCI/AGP Frequency(Mhz)
The values depend on PCI/AGP frequency.