Just as another side note...
Be careful when buying PC133 for a PC100 motherboard. Usually it will work, but other times it will not. It depends on the memory module. For example, if you look closely at the module(s) already in your system, you'll notice that they are either dual- or single-sided. Most PC133 chips are single-sided. So, unless you already have single-sided modules, I highly recommend you verify that the ones you are buying are "dual-sided" (they are more compatible with older motherboards).
Also, PC133 will only run at PC100 speeds (100MHz) on PC100 motherboards. There is no advantage of buying PC133 over PC100 in your case...
~cdogg
"The secret to creativity is knowing how to hide your sources."
- A. Einstein