I do the google thing too, and generally find just what I need. plugging the numbers on the individual chips themselves in, and searching through the semiconductor lists that pop up can help.
for example I have a SIMM here with:
SEC KOREA
525Y
KM48C2100AJ-70
the last number looks likely - about all I can tell straight off is it's 70ns. plugging the "48c2100" into google, I come across a page showing that as a:
IC-DRAM 48C2100,2MX8BIT,SOJ,28P,300MIL
looks like it - DRAM, same number, and 2m x 8bit
so basically each chip contains 2meg of 8bits, which in this case is an easy 2megabytes. There's 4 chips on it and that gives 8mb - I know it's an 8mb too cos it has a sticker on it that says 8MB
Another simm laying about has the string "HM5117400AS6" on it. 60ns there, and searching for "5117400" shows those chips being 4mx4, which is 4meg of 4 bits - for just sizing the chips that's equivalent to the first example too - it holds the same number of bits as a 2meg of 8bits - also, 2 of the 4megof4 chips would hold 4megof8bits, if that makes more sense, thinking in 8 bits
so with 2 chips holding 4 full megabytes, and 16 chips on the whole simm, it's... a 32mb simm.
98% of the time it's that simple. some ICs though, just don't turn up anywhere, and all I do there is stick them in a box and test
dana
