You need to change your multiplier.  So that your ratio is different.  When you overclock the FSB, you start with a multiplier ratio of something like 3:1 or whatever.  That means your RAM runs at 1x the speed, while your CPU runs at 3x.  You then look for the balance between your RAM's max speed and your CPU speed.  You can adjust these ratios to things like 5:2 or whatever, but eventually you just find the sweet balance between RAM speed and CPU speed.

  You may have to adjust voltages.  As you increase the speed, the power drain also increases.  This causes the CPU and RAM to say they are working at X speed, but performance will actually be worse because they can't get enough voltage to actually reach those speeds.  So you need to pay attention to the voltage as well and increase slightly when necessary.

  Of course, you have to have a BIOS that lets you tweak all that shit, otherwise you're kinda screwed.

I'm sad that I'm like the only one who isn't a hardcore computer phreak.  Oh well, you guys will help me next time my comp crashes and I need advice, right?  :)