PCI Express 4.0 controller: for now only for AMD X570 chipsets

The motherboard sector saw the presence of all Asian producers at Computex 2019 in Taipei, who have historically used this fair to announce their news. Obviously, the general interest was catalyzed by the proposals based on AMD X570 chipsets, which were designed to be combined with Ryzen 3000 processors equipped with Zen 2 architecture, which will make its market debut from 7 July.

The proposed models are characterized by classic form factors, including the Mini-ITX suitable for the most compact systems: however, most of them are of traditional ATX type in order to offer greater expandability as well as more complex components for the power supply part. For AMD Ryzen processors, we find in these motherboards the typical technical features of this type of product: at least two PCI Express 16x video card expansion slots, high external peripheral connectivity and support for both SATA storage devices and those with M.2 interface.

A PCI Express Gen 4.0 controller is integrated into the 3000 series Ryzen processors, which can offer twice the bandwidth in data transmission compared to previous generation solutions. Instead, a second PCI Express 4.0 controller is inserted into the AMD 570X chipset to provide incremental bandwidth not only in connection with the processor, but also to better manage other system-connected peripherals. The presence of this controller is the technical element that required the presence of an active fan cooling system for all the X570 motherboards we saw on the Computex: the chupset's TDP is actually equal to 15 Watts, a net increase figure compared to the X470 solution's 5 Watts.

AMD motherboards not based on X570 chipsets, belonging to the previous generation of 400 and 300 families, will not be able to use the PCI Express Gen 4.0 controller integrated into the new Ryzen 3000 processors, even though they are equipped with bios capable of supporting Zen CPUs 2. This decision is the result of the impossibility for AMD to ensure that motherboards of this type, when used in Gen 4.0 mode, are surely able to operate correctly with the specifications required by PCI Express devices.

Consequently, the combination of peripherals of this type, such as future Navi family AMD video cards, with Ryzen 3000 processors mounted on 400 and 300 series motherboards, will be possible with the PCI Express 3.0 interface and not the PCI Express 4.0 video and processor interface, but not the motherboard. That's why the next generation of SSD units with PCI Express 4.0 interface, based on Phison E16 controller, will require a X570 chipset motherboard to take advantage of its technical characteristics.