explanation of a divider?

you can only change it if you have the option in your bios. you should see the number "200" and when you change it, you can pick 183/166/133, etc. usually, you only want to use divider on cheaper ram with cl3. or if you are overclocking alot, then your ram might bottleneck and need to be lowered.

example
a 1:1 divider would be your FSB is 200MHz and your ram is running at 200 mhz
(DDR400)

you can change the divider to make your ram run at a lower frequency than your FSB so you can get higher CPU speeds with cheaper ram

An easy way to see if your running a devider is to look at CPU-z. Look at your HTT and then compare it to your memory speed. If they are the same, then your not running a devider (1:1). If the memory spped is higer or lower than your HTT, then your running a devider.

Dividers are used when you have one component that runs way faster than another component, a common one being the RAM and FSB. In your BIOS, you'll either see a couple of options for running your RAM. It'll be either in fractions (3/4, 5/6) or speeds (133, 166,200). If your BIOS runs dividers with fractions, just take the FSB speed you are running and multiply it by the fraction to get the RAM speed you would get (ie. 250mhz fsb x 5/6 = 208mhz RAM). If your BIOS runs dividers with speed grades divide the speed grade by 200 (default fsb) and then multiply by FSB (ie. 250mhz fsb x 166/200 = 208mhz RAM). Memory dividers are great when you have a board that can handle really high FSB speeds but the RAM cannot be OCed as high as the FSB. Ideally it would be great to run a 1:1 speed ratio FSB to RAM, but since that is hard to achieve, dividers are the next best thing.

here's how the overclocking guide defines RAM dividers.

Quote:
now i don't fully agree with this because i can gain more performance out of my current proc by running a 133 divider at tighter memory timings rather than running slightly looser timings and a higher memory speed.