PCI-E is the interface that allows the graphics card and other devices to communicate with the CPU. The 2200G only has 8 lanes of PCI-E 3.0 while the R3 1200 has 16 lanes of PCI-E 3.0. Now in practice, this isn't a huge problem as only the very highest end GPUs are likely to see any performance difference in the reduced 8 lane configuration, and on such GPUs, you're likely to be CPU bottlenecked first if you paired something like a GTX 1080Ti with a 2200G or 2400G. The Ryzen APUs also can't support SLI due to the PCI-E lane reduction, but that's once again a moot point as you would not try to run a high end SLI setup with a budget CPU.