AMD hints at Zen 3’s performance gains – Claims its an “entirely new architecture”

AMD hints at Zen 3's performance gains - Claims its an

AMD hints at Zen 3’s performance gains – Claims its an “entirely new architecture”

Zen 2 has been a gamechanger for AMD, enabling the company to make gains in every market segment where the architecture is available. Simply put, Zen 2 architectural changes and cutting-edge manufacturing have allowed AMD to be more competitive than they have been at any time in the past decade. 

While Zen 2 offered a tremendous leap for AMD’s CPU performance, AMD doesn’t expect things to slow down with Zen 3. In an interview with The Street, AMD’s Forrest Norrod said that Zen 3 would be an “entirely new architecture”, and that Zen 3 would be “right in line with what you would expect from an entirely new architecture.” This sets some high expectations for Zen 3. 

In the same interview, AMD’s Forrest Norrod stated that AMD was “confident [in] being able to drive significant IPC gains each generation,” and that AMD’s future server CPU launches would rely on a “tick-tock” cadence, which is something that Intel has failed to do for several years. 

We know that Zen 3 will a more mature version of the same 7nm manufacturing techniques that today’s Zen 2 processors are based on, making most of Zen 3’s performance gains due to architectural changes. 

Zen 3’s architectural changes

At the HPC AI Advisory Council’s 2019 UK Conference, AMD’s Martin Hilgeman confirmed that Zen 3 would move away from Zen/Zen 2’s split cache design, which split the L3 cache on AMD’s CPU dies between two quad-core CCXs. This suggests that AMD is making some major changes to its Zen core architecture with Zen 3, and lowering the barriers between the multi-CCX designs of today’s Zen processors. 

Instead of offering two L3 caches that are 16MB in size (as seen in AMD’s current Zen 2 design), AMD’s Zen 3 core design will offer a combined “32+MB” of L3 cache between all eight CPU cores. This will lower (or eliminate) potential inter-CCX latencies between the CPU cores in a single die and grant CPU cores better access to each chip’s onboard L3 cache memory. 

The slide below also suggests that Zen 3’s L3 cache will be bigger than what was seen in Zen 2. This means that Zen 3 could offer a larger, combine L3 cache, granting all CPU cores better cache access while also providing the potential for more cache capacity. This could lower some internal CPU latencies, and allow Zen 3 processors to cache more data on-die. These changes could be beneficial for Zen 3’s gaming performance, given AMD’s existing marketing for “GameCache”, and its benefits for Zen 2. 

Combine these cache changes with alterations to AMD’s Zen 3 compute units, and it is easy to believe that AMD will deliver a notable boost to Zen’s IPC with their Zen 3 processor designs. Today’s rumours place Zen 3’s IPC gains at 8-10%

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An 8-10% IPC gain with Zen 3 and a few 100 MHz in clock speed would make Zen 3 a decent upgrade over Zen 2, especially if Intel cannot adequately react to AMD’s HEDT and server-grade offerings. 

AMD’s Zen 3 architecture is due to release in 2020 for both the desktop and server markets. 

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