If this machine is more than one year old, I could make a bet it will not work with the 4GB stick or would not work well.
Let's use crucial.com to find what can be installed.
Bob
Hi i was thinking of getting a 4GB stick of ram to and i currently have 2x1GB sticks of ram so if i replace one stick with the 4GB ram would it be comparable?

Chowhound
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