A motherboard has 16 RAM slots and support quad-channel feature, with four RAM slots for each channel. All of 16 slots are black and labelled: A1, A2, A3, A4, B1, B2, B3, B4, and so on. How should one module of 4 RAM should be installed in order to take full advantage of the quad-channel feature?

Typically, the channels on a motherboard with multichannel support will be identified with a letter (A, B, C, D). Install one RAM module in each channel to take advantage of the multichannel features. Because the lowest-numbered slots are often filled first, you would use slot 1 (or zero, if numbering began there) of each channel. Of course, you should always consult the motherboard documentation.