You need to use a motherboard that supports a 133 mhz or higher front side bus. The gigabyte board you mentioned only supports up to 115 mhz.

863 mhz / 115 mhz fsb = a 7.5 multiplier (which i believe is the highest you can use on the board). You need something that can do 133 x 7.5 to equal 1000mhz (1 gig).