Don't you need an at-least-mediocre GPU to get high resolution on 3 monitors on any OS? I wouldn't connect 3 high resolution monitors to a Windows or Mac machine with no GPU.
The tradeoff is that the CPU half of AMD's processors is kinda bad - they are all derived from either Jaguar laptop processors or Bulldozer, they desperately need to be refreshed with Ryzen. So Intel has the better CPU but a mediocre GPU (unless you splash out for Crystalwell), and AMD has mediocre CPUs but a good GPU...
AMD's non-APU processors (FX, Ryzen, TR, Epyc) do not have iGPUs however, same goes for Intel's lines of server chips (X99/X299/etc). This is something that is only in "client" processors.