|Your manual doesn't seem to cover this but those pins are the clear cmos jumpers. The purpose of the pins is to reset the cmos to the default settings. This is sometimes useful if you have set one or more of the settings in the BIOS wrong, causing the computer to not boot.|
The proper procedure to use the feature is to first unplug the computer, then press the start button a couple of times. Then open the case and after grounding yourself, temporarily move the jumper from pins 1&2 to pins 2&3. Then return to pins 1&2.
Reconnect the power cord and start the computer. Immediately tap the proper key to enter the BIOS (setup) screens. I am guessing it may be the del key but consult your manual. Once there you will need to reset the date and time and possibly some other items, like boot order.