ASRock Rack's EP2C621D12 WS motherboard is just that universal case when you choose a platform for a machine for LGA-3647,
want to have a large number of PCI-Express slots and today's basic storage options. The main advantage of the motherboard is as many as 7 PCI Express 16x slots. As usual, clarification is required here: PCIE 3 and PCIE 4 slots share one x16 bus and work either in x16 + 0 format or in x8 + x8 format. The PCIE 2 slot operates in x8 mode, that is, there are actually 5 slots left for x16 speed, three of which you can use with 2-slot GPU cards without additional extension cords.