"It comes down to what system you have. Although a KT133/A and most Intel systems
will benefit from PC133 RAM, the price difference will always be there, although
being rather small. This particular PC100 module showed great performance for
a currently great price, so it is idealistic for PC100 only systems and pc users
who would rather spend less money on something that doesn't perform much worse"
FULL STORY @ HARDAVENUE (http://www.hardavenue.com/reviews/crucial128pc100.shtml)