AMD Zen4 IO core revealed for the first time

AMD's Zen4 architecture and CCD compute core design has been little secret, but the auxiliary IOD input and output core has been more mysterious.

Until the recent IEEE ISSCC International Solid-State Circuit Conference, AMD finally revealed its secret.

AMD Zen4 processors, whether consumer-grade Dragon, or server-grade Dragon, CCD part are TSMC 5nm process, up to 8 cores.

Among them, the sharp Dragon has 1-2 CCD, the number of cores 6-16; Roller Dragon has 2-12 CCD, the number of cores 16-96.

IOD are TSMC 6nm process, but sharp dragon, xiao long partner of very different.

The size of Rex here is only 12.4x9.5 = 117.8 square millimetres, about 3.37 billion transistors.

Xiao Long's is 24.8 x 15.6 = 386.88 square millimetres, twice as long, two-thirds as wide, almost 2.3 times as large, and the number of transistors is about 11 billion, also almost 2.3 times more.

CCD, IOD are counted, Zen4 sharp dragon processor integrated up to 16.5 billion transistors, the sky dragon reached a terrifying 90.2 billion!

Intel Sapphire Rapids fourth generation to the strong did not announce how many transistors, but certainly not so many.

In addition, Locuza_God also gave a detailed layout diagram of the Rex IOD label, you can see that it has only two groups of GMI3/IFOP3 interconnect ports, which means that only up to 2 CCDs can be connected, up to 16 cores, there can not be the legendary 3 CCDs, 24 cores.

The DDR5 memory controller is two groups of 40 bits, of which 32 bits are for the memory itself and the other 8 bits for ECC checksum error correction.

This means that all Raider 7000 processors will support DDR5 ECC, but it is up to the motherboard manufacturer to enable it or not.

The biggest area in the IOD is of course GPU related, although there are only two sets of CU units and 128 cores, but there are also display units, codec units and so on.

The others are the PCIe 5.0 controller, IO input and output units, power management, security controller, audio DSP and so on.