As is the case with just about every piece of RAM, it depends on the ICs used by Kingston in your particular sticks. Kingston is famous for using a wide assortment of chips to make their modules and in the PC2700 they have used, in addition to many others, Samsung, Infineon, Winbond and Hynix chips. Some of these are great overclockers, while other brands used by Kingston will barely do rated speeds.
Many of the chips used by Kingston are blanks and their is no way of knowing what they are and only testing will reveal their potential.
What are the codes on your chips?