How much RAM can i fit into my macbook?

Current series (and the last, though it won't use all of it) is 2 X 2GB, or 4GB total. So the max you can have if you have a single 1GB stick and don't want to replace it is 3GB (the original 1 X 1GB, + 1 X 2GB).

This info is all available on the Apple Support site for your machine, btw. All the major RAM resellers also have online configurators. Current street price for a full 4GB is $80-$100.

We have a Guide for this, and many other commonly asked questions.

Under the Guides tab at the top

Guides : Hardware : Understanding Intel Mac RAM

Odd that it was not helpful to you because it quite clearly states that the RAM limit is 4GB max. It also states that you can run either 1GB and 2GB sticks to acheive 3GB total or use 2 2GB sticks to make 4GB total (3-3.3GB visible).

The point here is you need to know what version of MacBook you have

If you have the 2.0 GHz machine, you could have a CoreDuo or a Core2Duo
You can tell under the Apple Manu : About this Mac

If it is the CoreDuo, you can install only 2 GB ( 2 x 1 GB SODIMMs)

If it is the Core2Duo, you can install 3 GB ( 2 GB + 1 GB ) or 4 GB ( 2 x 2 GB )

The early Core2Duos can recognize only 3 GD of the 4 GB if you were to install 2 x 2 GB. Starting with the SantaRosa models in 2007, they can recognize the full 4 GB

If this is the 2.0 GHz machine in your sig, then it is a Pre-SantaRosa and will recognize 3 GB only. There is a small benefit to installing the 4 GB because you will get a 6% - 8% speed boost from the matching pair.

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