Ever since AMD showed off its next generation Ryzen 7000 (Raphael) processors for socket AM5 , there has been some controversy regarding support for PCIe 5 and DDR5 interfaces. AMD has announced that the new processors will have full compatibility with both technologies, but the latest information shows that the chipmaker may hit a wall when it comes to chipset compatibility .
AMD has confirmed that its next generation flagship chipset, the X670E (E is for Extreme) is designed to have full compatibility with the PCIe 5 interface; On the other hand, we have the plain X670 chipsets, which would have optional PCIe 5 support for storage and graphics, while the mid-range chipset, the B650 , would only support the new PCI-Express interface in terms of storage.
AMD 600 chipsets pass PCIe 4.0 validation, but what about PCIe 5?
This week it came to light that the PCI-SIG organization had validated the interoperability of the AMD 600 Series chipsets for the AM5 socket (which, let us remember, is no longer PGA type to be LGA 1718) with PCI-Express 4.0 x4 a 16 GT/s, which may indicate that the chip logic of these chipsets may not support next generation PCI-Express 5.0. Keep in mind that the one in charge of designing AMD chipsets is ASMedia , so it would not be surprising if we end up with a different situation, since both companies do not use the same interface designs.
At the moment, the only chips PCI-SIG has validated for PCIe 5 are Intel‘s Alder Lake and Sapphire Rapids processors, as well as Intel FPGAs, Phison’s PCIe 5.0 redriver, Samsung 1743 SSD controller, and some modules from manufacturers like Broadcom, Cadence and Synopsis, but as you can see, AMD’s name is not on the list, so it should be a priority for Lisa Su’s company to validate its upcoming platforms.
Of course, AMD’s lack of validation with the PCIe 5.0 interface could mean that, as the AMD 600 Series chipsets are right now, we have a next generation AMD without support for the next generation of the interface, which is why which AMD would have to build a new revision later that does not have the shortcomings of the current ones and that is validated for PCIe 5.0.
Put another way, even though AMD Ryzen 7000 processors theoretically support DDR5 and PCI-Express 5.0 , if the motherboard chipset doesn’t support this technology it could mean that, at least initially, AMD might not release motherboards. compatible until later.
Can a supported but not validated board be released?
AMD has already announced with much fanfare that its next generation of processors (and motherboards, by extension) will feature up to 24 fifth-generation PCIe lanes, with up to 14 USB-C ports at 20 Gbps, support for WiFi E6 and Bluetooth 5.2 (also that the boards themselves will have HDMI 2.1 and DisplayPort 2 video outputs).
For this reason, it is difficult for AMD to back down at this point, so in response to the question in the statement, it is possible for AMD to launch compatible motherboards but without validating them. It could also happen that AMD simply delays the launch until it has validated its chipsets, or as we have assumed in the previous section, that it launches the new generation without initial support and then adds it in a later revision.
