Q:

How to know which RAM slots are in use in a Macbook Pro?

I'd like to upgrade the memory of a 15" Macbook Pro. It came with 4GB out of the box, but I don't know if it came as 1x4GB or 2x2GB.
Is there a way to know that, before unscrewing the computer?

A:

Open the Apple menu, select About This Mac. Then click on More Info… and select the Memory tab.

