News AMD Next-Gen EPYC Venice Zen 6 CPUs Reportedly Drop Into New SP7 Platform

[Admin]

Hardware leaker allegedly reveals some specifications regarding AMD's 6th Generation EPYC Venice CPUs with Zen 6 cores.

AMD Next-Gen EPYC Venice Zen 6 CPUs Reportedly Drop Into New SP7 Platform : Read more

 

[bit_user]

Given that market players like Intel and TSMC are experimenting with various innovative cooling systems for upcoming multi-chip solutions that will consume and dissipate well over 1 kW (1,000W) of power, we would expect AMD's CPUs in 2025 – 2026 to be in the same ballpark.

Something tells me their power efficiency is going to start putting them at a serious disadvantage, relative to ARM, if they let power consumption keep running away to such an extent.

Amazon's Graviton 3 uses just 100 W for 64 cores, for instance.

 

[edzieba]

Something tells me their power efficiency is going to start putting them at a serious disadvantage, relative to ARM, if they let power consumption keep running away to such an extent.

Amazon's Graviton 3 uses just 100 W for 64 cores, for instance.

Measuring relative performance merely by number of cores is about as useful as measuring GPU performance by number of fans.

 

[bit_user]

Measuring relative performance merely by number of cores is about as useful as measuring GPU performance by number of fans.

I disagree in that it's a modern, 64-core server CPU with 8-way superscalar cores & 2x 256-bit vector FP + 8-channel DDR5 + PCIe 5.0. That should give you a ballpark idea of where performance is at. For a more detailed comparison, people can go and find Graviton 3 benchmarks - or, they can even run their own!

The power data, on the other hand, is less readily available. Here's my source on it, BTW:

Amazon Graviton 3 Uses Chiplets & Advanced Packaging To Commoditize High Performance CPUs | The First PCIe 5.0 And DDR5 Server CPU

Shots are being fired at merchant silicon.Amazon's Graviton3 completely commoditizes generalized CPU compute while also bringing advanced packaging, PCIe 5.0, and DDR5 to the server market ~6 months before Intel and AMD.Server and rack level system architecture choices propel Graviton 3 to new...

www.semianalysis.com

While I'm at it, here are some benchmarks. If you want better ones, find them (or run them), yourself:

Amazon Graviton3 vs. Intel Xeon vs. AMD EPYC Performance Review - Phoronix

www.phoronix.com

There was a follow-on exploration of compiler tuning:

Amazon Graviton3 Compiler Tuning Benchmarks For The Arm Neoverse-V1 Cores - Phoronix

www.phoronix.com

 

[edzieba]

I disagree in that it's a modern, 64-core server CPU with 8-way superscalar cores & 2x 256-bit vector FP + 8-channel DDR5 + PCIe 5.0. That should give you a ballpark idea of where performance is at. For a more detailed comparison, people can go and find Graviton 3 benchmarks - or, they can even run their own!

The power data, on the other hand, is less readily available. Here's my source on it, BTW:

​

Amazon Graviton 3 Uses Chiplets & Advanced Packaging To Commoditize High Performance CPUs | The First PCIe 5.0 And DDR5 Server CPU

Shots are being fired at merchant silicon.Amazon's Graviton3 completely commoditizes generalized CPU compute while also bringing advanced packaging, PCIe 5.0, and DDR5 to the server market ~6 months before Intel and AMD.Server and rack level system architecture choices propel Graviton 3 to new...

www.semianalysis.com

​

While I'm at it, here are some benchmarks. If you want better ones, find them (or run them), yourself:

​

Amazon Graviton3 vs. Intel Xeon vs. AMD EPYC Performance Review - Phoronix

www.phoronix.com

​

There was a follow-on exploration of compiler tuning:

​

Amazon Graviton3 Compiler Tuning Benchmarks For The Arm Neoverse-V1 Cores - Phoronix

www.phoronix.com

​

I would recommend looking at the benchmarks you linked, as their comparison (16 core Graviton3 isntance v. 8 core Xeon instance) can vary wildly in comparative performance, let alone core-for-core performance, depending on the benchmark or workload.

Comparing core counts is a useful metric solely when comparing within the same architecture. Comparing between architectures is it effectively worthless. "More cores is more better" is great for marketing copy, but not much else.

 

[bit_user]

I would recommend looking at the benchmarks you linked, as their comparison (16 core Graviton3 isntance v. 8 core Xeon instance) can vary wildly in comparative performance, let alone core-for-core performance, depending on the benchmark or workload.

Comparing core counts is a useful metric solely when comparing within the same architecture. Comparing between architectures is it effectively worthless. "More cores is more better" is great for marketing copy, but not much else.

You're missing the point. A bit more or less performance per vCPU here or there doesn't change the fact that Graviton 3 has way better perf/W, which is all I was really trying to say.

This isn't directly relevant, because they quote whole-chip power but only rate-1 SPECint, but you can get some idea of IPC from it, if you normalize by clock speed:

Source: https://www.tomshardware.com/news/jim-keller-shares-zen5-performance-projections-kind-of
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Note: you might have to view the article version. I tried embedding what it linked as the source, but it didn't render in my forum post.

 

[edzieba]

You're missing the point. A bit more or less performance per vCPU here or there doesn't change the fact that Graviton 3 has way better perf/W, which is all I was really trying to say.

This isn't directly relevant, because they quote whole-chip power but only rate-1 SPECint, but you can get some idea of IPC from it, if you normalize by clock speed:

​

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Source: https://www.tomshardware.com/news/jim-keller-shares-zen5-performance-projections-kind-of​

​

Note: you might have to view the article version. I tried embedding what it linked as the source, but it didn't render in my forum post.

No, you're just looking only for what you want to see.
From your previous link, here's a workload where Gravtion3 pulls out well ahead (1.5x perf/core vs. the Xeon):

And here's one where graviton3 is utterly crushed (9.9x perf/core for the Xeon vs. Graviton3):

Workstation and server performance is HIGHLY workload dependant. The optimal architecture and CPU will vary wildly depending on what you are actually doing with the system. 'More cores is more better' is ignorant for consumer use, but outright incompetent for server and workstations.

 

[bit_user]

And here's one where graviton3 is utterly crushed (9.9x perf/core for the Xeon vs. Graviton3):

Workstation and server performance is HIGHLY workload dependant. The optimal architecture and CPU will vary wildly depending on what you are actually doing with the system.

That's not a simple matter of fundamental CPU ISA performance or micro-architecture. There's clearly something else going on there, which would need to be understood. Most likely, it some kind of x86-optimized code path that the test is stressing.

Unless delving into the particulars of that test case, such outliers should be trimmed.

'More cores is more better' is ignorant for consumer use, but outright incompetent for server and workstations.

Again, you're not seeing the forest for the trees. It's not about which CPU has better performance, but rather about perf/W.

Performance per vCPU is in the same ballpark, meaning Graviton 3 is a viable option for many or most workloads. It's not only cheaper because Amazon doens't have to pay the overhead of buying the CPUs from AMD or Intel, but also because they're cheaper to run. Better perf/W means lower cooling and direct power requirements.

If AMD and Intel start selling mainstream CPUs that burn 1 kW, they're really going to feel a backlash from the industry.

 

[edzieba]

If AMD and Intel start selling mainstream CPUs that burn 1 kW, they're really going to feel a backlash from the industry.

It's industry that are demanding ever-increasing performance density. It's no good having a 100W chip if you need 10 of them to do the work of a 1000w chip, whilst also taking up more rack space and paying 20x in per-core licensing fees.
Plus, with no independent benchmarking of actual Graviton3 hardware, the perf/watt claims from Amazon are best taken with a large fistful of salt (even if you have low-level but not physical access, reported figures can be quite far off actual draw).

 

[bit_user]

It's industry that are demanding ever-increasing performance density. It's no good having a 100W chip if you need 10 of them to do the work of a 1000w chip,

I think you missed the point about perf/W. Having better perf/W means like 2x or 3x 100 W CPUs doing the work of a 1 kW x86 one. That's a hypothetical example, but then so is yours.

whilst also taking up more rack space

The funny thing is that bigger power supplies and cooling solutions also take up space. So, a modestly higher number of significantly more efficient CPUs could actually come at comparable (or better) compute density. Amazon has 3x Graviton 3 CPUs per motherboard:

AWS Graviton3 Hits GA with 3 Sockets Per Motherboard Designs

Amazon AWS Graviton3 C7g instances are now in GA and are built upon a 3 CPU per motherboard design which is very unique

www.servethehome.com

and paying 20x in per-core licensing fees.

I seriously doubt most of the software running in the cloud has per-core licensing fees.

Plus, with no independent benchmarking of actual Graviton3 hardware, the perf/watt claims from Amazon are best taken with a large fistful of salt (even if you have low-level but not physical access, reported figures can be quite far off actual draw[/url]).

You're confusing mass market consumer garbage with servers. Consumer hardware can basically do whatever it wants, as long as it doesn't fry itself. Servers strictly adhere to their power envelopes, period. If a server uses more power than it's supposed to, that's going to get escalated as a critical issue by the biggest of big customers, who will be hopping mad until it's fixed. That's because not only does Watts = $$$, for those folks, but if you exceed the specs to which their cooling systems were engineered, it can lead to a lot of badness.

 

[edzieba]

I seriously doubt most of the software running in the cloud has per-core licensing fees.

Then you seriously doubt the majority of the HPC market.

You're confusing mass market consumer garbage with servers. Consumer hardware can basically do whatever it wants, as long as it doesn't fry itself. Servers strictly adhere to their power envelopes, period. If a server uses more power than it's supposed to, that's going to get escalated as a critical issue by the biggest of big customers, who will be hopping mad until it's fixed. That's because not only does Watts = $$$, for those folks, but if you exceed the specs to which their cooling systems were engineered, it can lead to a lot of badness.

No, you're confusing hardware sales with an Amazon-proprietary system. Since Graviton3 does not exist outside of Amazon-owned and Amazon-operated datacentres, Amazon can claim that a chip operates under whatever power budget they imagine, and nobody can independently verify that power consumption. Amazon can declare their '100W' figure is an absolute maximum power-virus package draw, or an 'average' draw, or a 'representative workload' draw, etc.
As for other server chips that anyone can hook power meters up to, the story also isn't as simple as there being a singular power draw value. This has not been true for many years, as individual cores will increase and decrease their clock speeds depending on thermal headroom (and not just per-package, but per unit die area within a package), packages will increase and decrease power budget allocations depending on chassis budget, etc. Thermal management is an integrated system-of-systems, not a bunch of independent units with a '#never exceed' limit and a big specced-to-maximum-possible-load cooling system. Nobody builds out a system that dumb anymore because its a huge waste of money. We're over a decade from the Open Compute Project demonstrating that there are more knobs to turn than just 'slap on a power limit' when it comes to optimising DC architectures for efficiency (from physical component layout to power distribution to non-phase-change cooling architectures, etc).

 

[bit_user]

Then you seriously doubt the majority of the HPC market.

That's not a big market, by cloud standards.

No, you're confusing hardware sales with an Amazon-proprietary system. Since Graviton3 does not exist outside of Amazon-owned and Amazon-operated datacentres, Amazon can claim that a chip operates under whatever power budget they imagine, and nobody can independently verify that power consumption.

It also means they have no real incentive to lie.