You heard right.
For some regular OCing, let's say you can take either....G. Skill or OCZ TCCD based RAM chips up to 290 FSB at 2.5-3-4-7 and it would be just as fast as 270 FSB at 2-2-2-7.
First you gotta see what RAM you have, TCCD based chips can OC very well, so can BH-5 (though you need much more voltage) and sinec you're already doing 2-2-2, I'm betting it's either TCCD or BH5. Try and hit 250 fsb with the tightest timings possible, most likely 2.5-3-3-7, and OCing is dependent on the amount of voltage, and especially your motherboard.
Name your motherboard and CPU, and it'll be a great starting point.