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AMD Zen Microprocessor Family

Concept WIKI v1 · 7/26/2026

The AMD Zen microprocessor family is a series of AMD CPU microarchitectures whose published errata have been systematically collected and analyzed by the RemembERR database. AMD documents errata on a per-microarchitecture (per-family) basis, in contrast to Intel's per-generation approach, and the Zen 3 family in particular contains documented post-production bugs such as a processor hang under specific instruction cache / Op Cache switching conditions.

AMD Zen Microprocessor Family

Overview

The AMD Zen family designates AMD's x86 CPU microarchitectures introduced from 2017 onward. In the context of design testing and validation research, the AMD Zen family is significant because AMD publishes a single errata document per CPU microarchitecture (per family), providing the empirical data on which post-production bugs are observed [chunk:82fcd5a6-2a96-493a-b0f8-8b0200af5adc].

Coverage in the RemembERR Database

The RemembERR project, presented at MICRO 2022, builds a comprehensive, annotated database of errata from Intel Core and AMD microprocessor families since 2008, totaling 2,563 entries [chunk:48681872-42d8-4875-aef0-49522abd34c6]. The corpus includes 506 errata from AMD, of which 385 are unique after de-duplication [chunk:82fcd5a6-2a96-493a-b0f8-8b0200af5adc].

Document Structure and Family-Based Publication

AMD organizes its errata documentation differently from Intel:

  • AMD uses a single document per CPU family (i.e., per CPU microarchitecture) [chunk:82fcd5a6-2a96-493a-b0f8-8b0200af5adc].
  • The publication cadence is family-based rather than generation-based, reflecting microarchitecture lineage rather than consumer-generation numbering.

Example Zen 3 Erratum

Table II of the RemembERR paper presents an illustrative AMD Zen 3 family erratum [chunk:66a76101-508a-40ba-93a0-78349cd409b3]:

  • ID: 1361
  • Title: Processor May Hang When Switching Between Instruction Cache and Op Cache
  • Description: Under a highly specific and detailed set of internal timing conditions, running a program with a code footprint exceeding 32 KB may cause the processor to hang while switching between code regions that consistently miss the instruction cache and code regions contained within the Op Cache.
  • Implications: System may hang or reset.
  • Workaround: System software may contain the workaround for this erratum.
  • Status: No fix planned.

This erratum exemplifies the conjunctive-trigger structure that RemembERR identifies across virtually all collected errata: multiple specific conditions (instruction cache misses, large code footprint, internal timing) must simultaneously occur to trigger the bug [chunk:66a76101-508a-40ba-93a0-78349cd409b3].

Design Testing and Validation Implications

Errata from the Zen family and other AMD microarchitectures contribute to RemembERR's broader observation that trigger conditions in errata are conjunctive while contexts and observations are disjunctive [chunk:48681872-42d8-4875-aef0-49522abd34c6]. This insight guides test engineers toward constructing input stimuli that exercise multiple trigger conditions simultaneously to surface post-production bugs in Zen-family processors.

Cross-Vendor Distinctness

Because Intel and AMD designs are proprietary and likely do not share hardware blocks, identical bug instances across vendors are unlikely [chunk:82fcd5a6-2a96-493a-b0f8-8b0200af5adc]. This makes the AMD Zen family an independent source of errata evidence that complements, rather than overlaps with, Intel's published bugs.

LINKED ENTITIES

2 links
RemembERR: Leveraging Microprocessor Errata for Design Testing and Validation EVALUATES
AMD MENTIONS

CITATIONS

4 sources
4 citations
[1] RemembERR contains 506 errata from AMD, of which 385 are unique, including entries from AMD Zen family microarchitectures. Leveraging Microprocessor Errata for Design Testing and Validation
[2] AMD publishes a single errata document per CPU family (per microarchitecture), in contrast to Intel's per-generation approach. Leveraging Microprocessor Errata for Design Testing and Validation
[3] AMD Zen 3 family erratum 1361 documents a processor hang when switching between instruction cache and Op Cache under specific timing conditions and code footprints exceeding 32 KB, with no fix planned. Leveraging Microprocessor Errata for Design Testing and Validation
[4] RemembERR's database of 2,563 errata covers Intel Core and AMD microprocessor families since 2008 and is used to identify gaps in design testing and validation. Leveraging Microprocessor Errata for Design Testing and Validation