User guide

Magnum N270 Installation
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Jumpers
The processor board used in the MAGNUM N270 PC is largely free of selection jumpers. Most settings are
controlled from the BIOS, and stored in the CMOS memory.
Figure 3: Jumper Locations
Only the following jumpers are significant.
CMOS Clear
To clear the CMOS memory, first switch off the PC power, then locate the 3-pin header labelled ‘CLRTC’ on
the processor board which is beside the battery connector. Remove the link shorting pins 1 and 2, and place it on
pins 2 and 3 for about 5 - 10 seconds. Remove the link and replace it in its original position. The CMOS has
now been cleared and the BIOS will be reset to the default settings.
Having no link fitted is an invalid option.
Figure 4: CMOS Jumper
JAT Power
The JAT jumper determines AT (automatic power ON when power applied) or ATX (power on by front panel
switch) operation
JAT
Mode
Open
ATX Mode
Short
AT mode