This particular mobo has its J26 I think, positions from 1 to 4, whereby the position 3-4 cannot be set due to missing pins = thus cannot set 512KB cache option, though there is a printed table of values on the PCB. Do you think by soldering these two joints I could possibly get what i want?

We can see multiple missing jumper pads, but I only miss 2 in the very left side, where the jumper is set over the existing position 2 and non-existing position 3.

The stason link just for sure http://www.lejabeach.com/Biostar/MB-8Series/MB-8433UUC.htm

Also if we have a empty place for a PC buzzer, can I add one on it with functioning results?