If you start on Crucial's homepage click here and use the Memory Advisor tool, and then enter the information for your netbook (Acer, Aspire Netbooks, Aspire One) you will come to the memory that I linked to.
Note that at the top of the page it states "Guaranteed-compatible memory upgrades for your Acer Aspire One Netbook." Can't say fairer than that. That means that if they supply the memory then they will guarantee that it will work. If you source the same specification memory from another company however, you are on your own.
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