How do you determine which RAM slots are active on a ...
Typically, motherboards have a total of 4 RAM slots or two pairs when they are dual-channel. Some high-end motherboards may contain as many as eight slots, and in supercomputers, there may be multiple motherboards per system, up to 32 slots total.
Micro ATX Motherboard Guide - Important Facts You Should Know
Within each generation, all chips work on the same motherboards, use the same kind of RAM, and have the same architectural advantages - with one key exception.
Potential problem with RAM slot
If you have four RAM sticks and a four-slot motherboard, then you can just populate all four slots with all four RAM sticks.