All revisions, as far as I know, of the slot-loading G3 can handle 2x512 PC100 to get 1GB of memory.
See here.
ok, here's the thing.. I bought this system from a vendor who sells 2nd hand Macs. I dun know if they've swap anything from the inside. I suppected that the optical drive and the HDD was swapped. How do I check the model and batch number?