The 320 chipset was meant for an office only environment whereby it meant everything was watered down. The only reason that they were included into a "Gaming" portfolio was to induce sales of the chipset or board. In reality that board can't do any form of overclocking, ram overclocking is limited and that will depend on the processor's IMC as well.
I'd advise not tinkering with BCLK. If the boards are expendable, then you might want to look into other areas of the BIOS since they can be listed under a different terms or branch of the BIOS.