The dividers are the same as ratios. Think of your old math class simple division. For example, if the ram is set at at 333 and the cpu fsb is 666, then the ratio works out to 1:2. I try to run the ram at spec when overclocking, which may require me to drop the ram speed below spec in order to increase the cpu fsb. Normally, when you raise the cpu setting, the ram follows by the same percent, if that makes sense. With locked dividers, you'll know what setting to use ahead of time so you can maintain the correct ratio and your system won't crash by a bad setting. Most boards don't give you the option of using dividers, they select the ratios automatically to keep the system from crashing. But if you set the cpu fsb too high, then your system won't post, and you'll have to reset the bios and start over.