But the way they wired it up, makes it a really weird choice over almost any X570 board imho. I mean, who wants three PCIe 4.0 NVMe drives, but are willing to compromise on the graphics card lanes to x8? Yes, I know it makes nearly no difference whatsoever in game, but considering how many people out there are screaming that Intel is better for gaming because you get 2-3% more performance on average, then this would give you a further 2-3% disadvantage.
I just find it a really odd product in every way possible.
I actually think it's a very clever way of wiring up and using all the available resources of Ryzen SOC + B550. Ryzen SOC provides 20 usable PCIe gen4 lines, B550 provides 10 usable PCIe gen3 lines, of those 10, 2 are shared with the 5th and 6th sata ports. This board wires 4 of the gen4 lines to the first m.2 slot and the other 16 of the gen4 lines go to the GPU slot, or 8 to the graphics slot and two x4 to the m.2 slots 2 and 3 if used. 8 of the gen3 lines of the chipset are wired to the other two expansion slots.
The interesting thing is this: The first m.2 slots is x4 dedicated to the CPU. Now if you want additional m.2 drives you have the option of them being gen4 using the provided m.2 slots but obviously, as there are no more dedicated gen4 lines available, you have to share the ones to the GPU, so the GPU runs at gen4 x8. If the GPU supports gen4 like the RX 5700 of AMD and the upcoming nvidia generation then you have the same badnwidth as gen3 x16 which is more than plenty. But you have the option of pluggin the m.2 to the other expansion slots wired to the chipset as gen3 using one of
these very cheap pcie->m.2 adaptors.
So, long story short, this board in my opinion offers the best possible use of the available resources in B550: first m.2 gen4 dedicated, the others could be gen3 with adaptor on pcie slot or gen4 sharing gpu bandwidth. Now that gpu cards are supporting gen4 this is a non issue.
P.S: We are talking about the B550 AORUS Master, forgot to add.