Hi, first post (hello).
My build will use two out of four DIMM slots, and I found two sources that seemed to suggest opposite configurations as the ideal. I figured out what was going on and wanted to share it (easy mistake).
The board is the AsRock B650D4U (and its variants).
The first source is the user manual for the motherboard which suggests A1, B1 as the ideal slots used. (page 25)
The second source is an overclocking forum post that suggests A2, B2 is the ideal for two RAM sticks.
(I’m unable to post links. It’s on MSI, thread title is “RAM explained: Why two modules are better than four / single vs. dual-rank / stability testing”)
To quote the post:
Note: Never populate slots 1 and 3 first. When putting the modules into slot 1 and 3, the empty slots 2 and 4 would be like having some loose wires hanging from the end of each RAM contact, creating unwanted signal reflections and so on. So with two modules, they need to go into the second slot (slot 2+4, or A2 and B2) of each memory channel, to not have “loose ends” after the RAM module.
It looks like contradictory advice, but when I looked at the mobo layout in the manual, A1 and A2 were inverted from most RAM diagrams I’ve seen. (Page 7)
It’s a simple mistake with a simple fix. Just wanted to share this in case people with this board have slots 1 and 3 occupied instead of 2 and 4.