It means that you should be running your memory at 1/1 and anything other than that will hurt performance somewhat. Running at various cpu/ram multipliers will give different results, and who knows what the mobo and memory controller is doing when running asyncronously.
You might try running the memory at 1/1, and if it's not stable you might be able to increase the memory timing until it is stable, but then you're slowing it back down again. Once you get into overclocking like that, you pretty much need to make a change and test it to see if the change helped at all. If you do in fact get your best performance with a 260 FSB and 3/2 cpu/mem ratio, then just go with it.
Some AMD guys are pushing FSB up past 300 to get the mobo running as fast as possible, then dropping cpu and memory multipliers to where they function properly. But different systems respond to that sort of thing in different ways so you just gotta figure out what works best for you.
Also keep in mind that if you're getting decent overclocking results on what you already have, tossing more money at faster components probably won't get you all that much of a performance increase.
