Diagrams of what appears to be AMD’s X390 motherboard have leaked out from Reddit (via Videocardz) and show details of the PCIe lanes as well as CPU/chipset control. The more interesting part of the leak however, is the alleged X399 motherboard. This is something that is supposedly going to support the 16 core processor from AMD and is interesting to see it pop up again in another rumor.
Will we be seeing a Naples-like chip on the LGA socket? Alleged AMD X390 and X399 motherboards detailed
The validity of this particular diagram is certainly not a given considering the source and the fact that it would be easy enough to doctor with anyone that has a (very) substantial amount of free time. That said, this is the second time we have heard of the X399 motherboard and usually there is no such thing as a coincidence in this field. Let’s start with the X390 diagram however.
The X390 motherboard is an ASUS mobo, as is clear by the AURA RGB control chip (which can be spotted next to the PCIe slot). The presence of the RGB controller means that this is a gaming motherboard. This also means that if this leak is legitimate then the company responsible for this is, you guessed it, ASUS. Whoever leaked the diagram did add the colors in to the monochrome drawing to point out which lanes were controlled by the CPU and which by the chipset.
The socket in question is surprisingly titled the AM44 socket (which I have never heard of). It is possible that this is referring to a proprietary socket (like the ASUS OC Socket) with some modified configuration of the seat to allow for claims of improved performance. Or, like VCZ mentions, it could be just a simple typo.
Here is finally, the X399 motherboard, the more interesting of the two. This is a 2S (dual CPU) capable motherboard that will supposedly house the 16 core processor that AMD is apparently cooking up on an LGA socket. The X390 is the single CPU variant of the same. It is possible that what these leaks are essentially talking about is the Naples processor, although preliminary reports stated that it will be on the AM4 socket and certainly not any LGA design. We can see the diagram has ECC memory support. Unlike the X399 however, the X390 has PCIe lanes connected directly to the chipset. The X390 chipset would support up to 44 PCI Express lanes. That would be even more than Intel’s flagship Core i7 6950X on X99 platform (40 lanes).
The Naples chip of course has been spotted multiple times on Zauba’s shipping database. The Summit Ridge platform is AMD’s mainstream platform with Zen architecture and 8 core dies. Naples on the other hand is the codename of the server platform; the very same platform which will be rocking Zen in 32 core flavor. This is not to be confused with the Zeppelin platform which will include a 32 Zen core/Vega based APU as well. The 32 Zen cores are tied together using AMD’s very own Coherent Fabric. The homegrown interconnect will support data rates of upto 100GB/s which is a lot faster than what the PCIe interface sustains (around 15GB/s). Not only that but latency has been reduced from 500ns to an unknown but allegedly smaller number.
Here’s the thing though, this very same lego-like build philosophy can allow AMD to roll out a 16 core variant in the commercial space as well, since both utilize the same socket, it really shouldn’t be an issue at all. In fact, yield theory dictates that AMD can roll out any number of cores from harvested dies from failed Naples chips (this includes 10 core, 12 core and yes even 16 core chips).
Interestingly however, the rumor says that such an SKU might be based on the LGA socket – that would increase the difficulty of porting and conflicts with AMD’s current philosophy and is the one thing that makes me doubt the authenticity of this rumor. That is to say that AMD can easily roll out a 16 core Ryzen processor but its not going to be based on LGA – for that to happen, it will need to revamp everything from scratch and create a new socket (which this rumor dubs as the X399 socket).