Thank you Paul for your very fast reply and solution.
The reason I was unsure is that the maintenance manual supports 8 GB memory, but then the listed configurations do not include the option of 2x4 GB.
However, your mail confirms that I can have 2x4 GB, provided the memory is as you specify, i.e. 2 x 4 GB of PC3-10600 memory, not exceed 1333 MHz, and the memory modules have to have 8 of the little black memory chips on each side of the circuit board, not 4.
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