Zen 2 core vs uncore/SOC

[porina]

As subject, is there a reference somewhere the details what is included under which part of Zen 2, specifically core or uncore/SOC? I've unsuccessfully tried to find one. 

 

Edit 15 Mar 2021

Apparently AMD does use the term uncore too.

 

Forrest Norrod, Senior Vice President and General Manager of the Datacenter and Embedded Solutions Business Group:

Quote

The I/O die in current EPYC systems is synonymous with what we call the uncore - essentially everything that is not part of the core. In general we’re trying to drive far more innovation around power management and power efficiency in the uncore. You’re going to see us continue to drive the process node very hard on both the cores as well as the uncore. We’re going to continue to drive innovation around the interconnect. So Infinity Fabric as a protocol has got a lot of legs, but you’ll see us continue to do things to make that more and more power efficient, and lower the picojoule per bit of switch traffic.

https://www.anandtech.com/show/16548/interview-with-amd-forrest-norrod-milan

 

[Bombastinator]

*doesn’t know what uncore even is.  Sounds suspiciously like a marketing term*

[Coolmaster]

5 minutes ago, Bombastinator said:

*doesn’t know what uncore even is.  Sounds suspiciously like a marketing term*

Seems like Intel marketing for their not directly computing parts of the CPU https://en.wikipedia.org/wiki/Uncore

[Bombastinator]

6 minutes ago, Coolmaster said:

Seems like Intel marketing for their not directly computing parts of the CPU https://en.wikipedia.org/wiki/Uncore

Ah.  I’ve heard of system agent.

[porina]

SoC/Uncore is used in Asrock's BIOS. Ok, it looks like SOC is the more common term for AMD, but the same question remains, what is covered under Core and Soc?

[Bombastinator]

14 minutes ago, porina said:

SoC/Uncore is used in Asrock's BIOS. Ok, it looks like SOC is the more common term for AMD, but the same question remains, what is covered under Core and Soc?

I would assume (which is rarely a safe thing to do) that core would be the actual processor bit.  So northbridge, southbridge, and possibly other stuff too.

 

historical background stuff that is probably not useful to many

Spoiler

 There used to be only single for chips, then it was discovered that adding multiple actual processor sections to a single chip could allow those “cores” to share support electronics and make everything faster.  Thus “multi core” CPUs were borne.  Things that were previously not on the main die were also added to it.  Most famously northbridge and southbridge functions though there were also other things.  Such chips that had both north ridge and southbridge on die were known as SoC, or System on Chip.  This could refer to everything BUT the computing cores or only part of them.

 

Edited November 23, 2020 by Bombastinator

[Mateyyy]

9 minutes ago, porina said:

SoC/Uncore is used in Asrock's BIOS. Ok, it looks like SOC is the more common term for AMD, but the same question remains, what is covered under Core and Soc?

I think that might just be the first time I've seen the SoC being referred to as Uncore on Ryzen... just Asrock things I guess? lol

 

I'm not very familiar when it comes to overclocking and what each specific voltage does on Ryzen, but as far as I'm aware, Vcore powers the CCXes/CCDs (so the actual cores and cache?) and the SoC powers the iGPU, memory and the Fabric (or I guess you could say it powers the I/O die..?).

 

34 minutes ago, Bombastinator said:

*doesn’t know what uncore even is.  Sounds suspiciously like a marketing term*

Uncore is what several motherboard manufacturers refer to the cache as on Intel platforms (at least on mainstream). It's also sometimes called ring.

For example, on Z490, ASUS calls it "Cache", MSI calls it "Uncore" and Gigabyte calls it "Ring".

[porina]

12 minutes ago, Bombastinator said:

I would assume (which is rarely a safe thing to do) that core would be the actual processor bit.  So northbridge, southbridge, and possibly other stuff too.

On Intel side, core would cover between execution units through to L2. The L3 cache and memory controller are separate. I just realised I didn't understand how it might be split on AMD, and in particular Zen 2. I think it is safe to assume the core would also cover execution units through to L2 at the least, but does it also include L3? IF on the core CCD?

 

Actually, the screenshot I gave suggests that IF is covered by SOC, so that only leaves L3 under question.

 

8 minutes ago, Mateyyy said:

I think that might just be the first time I've seen the SoC being referred to as Uncore on Ryzen... just Asrock things I guess? lol

At least I wasn't making it up myself. Must have thought "uncore" after seeing it there, not realising it may be more of an Intel term.

 

8 minutes ago, Mateyyy said:

I'm not very familiar when it comes to overclocking and what each specific voltage does on Ryzen, but as far as I'm aware, Vcore powers the CCXes/CCDs (so the actual cores and cache?) and the SoC powers the iGPU, memory and the Fabric (or I guess you could say it powers the I/O die..?).

I don't think it is separated by die, but by function. IF is listed as covered by SOC in the screenshot earlier for example, and IF would be present on both CCD and IOD. I think that only leaves L3 cache under question if it falls under core or SOC. As far as I'm aware, there is no separate setting for L3 cache speed on Zen. I have a feeling it is tied to IF, so would that make it soc side if that is correct.

 

8 minutes ago, Mateyyy said:

Uncore is what several motherboard manufacturers refer to the cache as on Intel platforms (at least on mainstream). It's also sometimes called ring.

For example, on Z490, ASUS calls it "Cache", MSI calls it "Uncore" and Gigabyte calls it "Ring".

Yup, the L3 ring cache was on a separate clock/voltage domain from the cores on Intel consumer. I just wish I knew what happens in Zen 2.