HP (Hewlett-Packard) 520 5/XX Personal Computer User Manual


 
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2 System Board - (SiS Chipset) (Part Number: D4051-63001)
SiS Chipset
SW2 Switch
This switch is used to select the internal CPU frequency by defining the CPU
Bus Frequency / CPU Frequency ratio. If the processor is upgraded, the
ratio might have to be changed to adapt to the new processor.
The following table includes some examples of the settings to use for
different processor speeds:
The default settings for Switch 2 and Jumper J7 depend on the
particular HP Vectra 500 Series PC model.
CPU Bus Frequency Jumper
This jumper (J7) defines the CPU bus frequency. The following illustration
shows how to set the desired bus frequency.
Processor Speeds
Switch Block SW2
Position
Jumper J7 Settings
Ratio
1 2 CPU Bus
Frequency
Pins Shorted
CPU Frequency 100 MHz 2 / 3 OFF OFF 66 MHz 3 - 4
CPU Frequency 120 MHz 1 / 2 ON OFF 60 MHz 1 - 3
CPU Frequency 133 MHz 1 / 2 ON OFF 66 MHz 3 - 4
CPU Frequency 150 MHz 2 / 5 ON ON 60 MHz 1 - 3
CPU Frequency 166 MHz 2 / 5 ON ON 66 MHz 3 - 4
4
3
1
4
3
1
4
3
1
50 MHz 60 MHz 66 MHz