Inquiring into the new graphical driver of AMD Radeon for Linux, it has been discovered that the company seems to have in mind that its new graphics cards for computing, the AMD Vega 20, will support the standard PCIe 4.0. If so, the use of this data bus would effectively double its available bandwidth.
Despite having been officially presented at the beginning of June of last year 2017, the reality is that currently there are not too many components in the desktop segment that use the PCIe 4.0 bus. Just as there was virtually no significant time difference between the announcement of the PCIe 2.1 standard and the introduction of the PCIe 3.0 standard, this time it has been four years since the PCIe 3.1 was announced until 4.0.
However, as we said, in the desktop market there are no components that can use this standard, mainly because there are no motherboards that support it. At the moment, all motherboards are still anchored in the PCIe 3.0 standard for many years. But, the reality is that the PCIe 3.0 bus at no time has given symptoms of lack of bandwidth for the components that are usually connected to it.
The discovery has been made when we have seen the modification of the PCIe bus driver that uses Linux, where an entry has been added so that the AMD Radeon graphics cards support the PCIe 4.0 bus. Obviously, we are aware that this modification of the driver does not imply that this will apply to the new AMD Vega 20. But if we join this information, with a previous one that said that these cards should be available from the third quarter of this year, in parallel to the new AMD EPYC Rome processors, then the answer would be – YES they would be compatible with this data bus. And knowing that the environment in which more are to use these cards is that of servers, it is easy to see where the shots go.
For practical purposes, the PCIe 4.0 bus doubles the available bandwidth for the devices connected to this data bus, which goes from the 8 GT / s of the current PCIe 3.0 bus to the 16 GT / s (so you can get an idea, the PCIe 1.0 bus had a bandwidth of 2.5 GT / s), but maintaining a total retro compatibility with the previous standards. This makes us suspect that the new AMD Vega 20 would need a greater bandwidth than is currently able to provide a PCIe 3.0 x16 slot.