Thanks.I think he means processors have a limit on RAM. For example, one might have a limit of 1gb but you've got 4gb installed, the processor would only use the first 1gb, the remaining three would be redundant.
PS... I'm a novice too
As I'm a light user I'm sort of relying on the manufacturers not making a machine that will only last a short time. If I knew that I downloaded like mad and also had a load of stuff to store, I'd be looking at different necessary features.

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