anyone know what the s stands for in pc2-6400s, i have a laptop with 2x1gig marked s ,and i wanted to upgrade so i got the shop to order me a 2gig stick ,but it doesn't have the S , i installed it ,seems to be working ok,but didn't make any difference between the 2gig and running at 3 gig .is the S a important factor ,thinking maybe it just for sodim, the s chip is samsung ,the 2 gig i bought is kingston.will eventually get another kingston to make it an exact match

and yes Bob i did google it 10 different ways , ,one forum poster actually said it was singular and plural !

No one explains it but I see lots of references to the 's' and when I google w/o the 's' I get a different set of results.

I can't see what the difference is, sorry.

thank you ,i searched and searched and find nothing .