According to this the tech spec states DDR2 at 667Mhz. If you have the exact model number of your machine, then you can search for the tech spec which will tell you exactly what type of memory is supported and how much memory in total the board can take.
Not having much luck finding anything with those numbers.
Is this a really old laptop? I ask because what I can find suggests that it has 128MB or memory soldered and can be upgraded to a total of 384MB by buying an additional 256MB PC133 133Mhz SDRAM SO DIMM 144-pin.