Tuesday, December 26th 2017
AMD 400-series Chipset Surfaces on PCI-SIG, PCIe 3.0 General Purpose Confirmed
AMD's second-generation Ryzen processors, which debut some time in Q1-2018, will be accompanied by the company's new 400-series motherboard chipset, even though they are expected to work with existing socket AM4 motherboards based on 300-series chipsets (with BIOS updates). The 400-series Promontory chipset surfaced on the PCIe Integrators List of PCI-SIG, the standards governing body of the PCI bus (which also oversees PCIe specifications development).
The listing seems to confirm that 400-series chipset will feature PCI-Express gen 3.0 general purpose lanes. These are downstream PCIe lanes put out by the chipset, to run the various external onboard controllers on the motherboard, and usually wired to the x1 and x4 PCIe slots. The current 300-series chipset only features up to 8 PCIe gen 2.0 general purpose lanes, and that was seen as a drawback. AMD Ryzen socket AM4 processors put out additional gen 3.0 lanes besides the 16 lanes allocated to PEG (one x16 or two x8, physically x16 slots); and 4 lanes serving as chipset bus. These additional gen 3.0 lanes typically drive a 32 Gb/s M.2 slot. With 400-series chipset bringing gen 3.0 general purpose lanes, one can expect newer socket AM4 motherboards with more than one 32 Gb/s M.2 slot (one from the SoC, another from the chipset).
Sources:
PCI-SIG Integrators List, VideoCardz
The listing seems to confirm that 400-series chipset will feature PCI-Express gen 3.0 general purpose lanes. These are downstream PCIe lanes put out by the chipset, to run the various external onboard controllers on the motherboard, and usually wired to the x1 and x4 PCIe slots. The current 300-series chipset only features up to 8 PCIe gen 2.0 general purpose lanes, and that was seen as a drawback. AMD Ryzen socket AM4 processors put out additional gen 3.0 lanes besides the 16 lanes allocated to PEG (one x16 or two x8, physically x16 slots); and 4 lanes serving as chipset bus. These additional gen 3.0 lanes typically drive a 32 Gb/s M.2 slot. With 400-series chipset bringing gen 3.0 general purpose lanes, one can expect newer socket AM4 motherboards with more than one 32 Gb/s M.2 slot (one from the SoC, another from the chipset).
30 Comments on AMD 400-series Chipset Surfaces on PCI-SIG, PCIe 3.0 General Purpose Confirmed
So, TB is already a terrible choice for latency. If the PCH had the bandwidth, adding a little more probably wouldn't kill it however, you might want it connected to the CPU for the very reason that you're already dealing with a lot of latency because of how it works. So, there are trade-offs whatever way you go. I think that GPUs over TB is the exception, not the rule so, I would probably say, not the CPU if CPU PCIe lanes are at a premium. The cost of having it go through the PCH is probably not very high though because latency sensitive applications will already be suffering over TB compared to being in an actual PCIe slot.
Look at that, Intel's chipsets apparently only supports four PCIe slots as well if I read this like some of you do...
That's not what it says though, it says that the maximum lane width is a total of four lanes, i.e. the chipsets can ad the most provide a x4 slot, i.e. for an M.2 NVMe slot for example...
This doesn't say anything about how many lanes the chipsets provide, at all.
I think you all need to take a chill pill and read things before posting angry comments about things you don't fully understand.
Simple fact is: Z370 motherboards offer up to three M.2 x4 slots (or two M.2 and Thunderbolt 3). X370 variants (even put in the same segment - like AsRock Taichi) offer a single M.2 x4.
Question is:
What the hell is the point ?, it offers no performance, it increases the latency and decreases performance thus it's pointless you might aswell have NVME to SATA at this point.
Intel says up to 24x pci-e through chipset or something while it's limited by 4X to the rest of the system so I wonder... what is the point of it all? sharing 4x on 2 drives is ok, but 3 drives, usb, sound, network, sata+++ then you start getting into a serious x4 bottleneck >_<
AMD's approach is easier: everything has almost dedicated bandwidth.
Not that I'd want to see two cool fancy 4X on the boards but in theory if ryzen 2 comes with PCI-E 4.0 the existing nvme and pci-e slots should be pci-e 4 on 300 series boards but not to chipset, free upgrade on older chipsets too.
Thus making gpu and other pci-e slots also pci-e 4.0 for those not through chipset.
Hopefully that is what happens :)