[Venn1]

Is there anything (technically) preventing SBC manufacturers adding SODIMM slots?

I was expecting the Milk V Titan to avoid this memory nonsense since it has two unpopulated DDR4 slots, but it has fallen off the radar like several other SBCs.

[murderfs]

SODIMMs are huge compared to a BGA memory package which is a problem if your goal is to minimize your board size (e.g. I don't think there's a reasonable way to fit it into a Raspberry Pi form factor without something weird and expensive like a mezzanine connector). Routing the signals is also somewhat more annoying because they all come out of one edge of the connector compared to a BGA package which has them fan out in every direction, giving more space for length matching traces, etc. You'll likely need additional PCB layers compared to a BGA chip.

[tempest_]

DDR4 is also crazy expensive right now so this just depends on you having some around from a previous build

[zozbot234]

It actually seems to be slightly less expensive than DDR5, perhaps due to the lower throughput that makes it uncompetitive for AI-adjacent workloads.

[deltoidmaximus]

If you're willing to check the used market it is more affordable as the spike isn't as severe as used DDR5.