Can you be slightly more specific as to which model it is?
There is a dutch site that you can use to search what type of memory you need (can use) to upgrade nearly any laptop.
I tried the site for you but I found that all toshiba satelite 2800 series are PC100, furthermore some will only let you upgrade by 128MB.
Here is the site you can try it if you want, even if your dutch isn't that good you should be able to find your way through it, dutch is a lot like english.http://www.geheugen.com/memoryzoek.asp
A short guide:
selecteer = select
merk = brand (make)
type = type
Standaard geheugen = standard memory
Maximaal te installeren geheugen = maximum amount memory that can be installed (Including any that cannot be removed)
Aantal uitbreidingssloten = number of expansion slots
Hope its helpful
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