Well one thing to consider is undervolting. If the Ryzen 2200G and 2400G are anything like all the currently-available desktop Ryzen CPUs, then putting them into at least a B-series motherboard should let you undervolt (assuming the board itself supports that capability!)
It'd also be ideal to get a board that supports offset voltage rather than absolute voltage since the former will be applied even when the processor is at low idle clockrates.
Speaking of offset voltage, you can sometimes achieve somewhat to considerably greater offset-undervolts if you also underclock the processor a bit. I don't remember the exact offsets off the top of my head, but my G3258 needs an offset voltage somewhere around -0.110v at its stock 3.2GHz, but at 2.9GHz it only needs something like -0.170v.
It'd also be ideal to get a board that supports offset voltage rather than absolute voltage since the former will be applied even when the processor is at low idle clockrates.
Speaking of offset voltage, you can sometimes achieve somewhat to considerably greater offset-undervolts if you also underclock the processor a bit. I don't remember the exact offsets off the top of my head, but my G3258 needs an offset voltage somewhere around -0.110v at its stock 3.2GHz, but at 2.9GHz it only needs something like -0.170v.
Dolphin 5.0 CPU benchmark
CPU: Xeon E3-1246 v3 (4c/8t Haswell/Intel 4th gen) — core & cache @ 3.9GHz via multicore enhancement
GPU: Intel integrated HD Graphics P4600
RAM: 4x8GB Corsair Vengence @ DDR3-1600
OS: Linux Mint 20.3 Xfce + [VM] Win7 SP1 x64
CPU: Xeon E3-1246 v3 (4c/8t Haswell/Intel 4th gen) — core & cache @ 3.9GHz via multicore enhancement
GPU: Intel integrated HD Graphics P4600
RAM: 4x8GB Corsair Vengence @ DDR3-1600
OS: Linux Mint 20.3 Xfce + [VM] Win7 SP1 x64