diff --git a/CHANGES.rst b/CHANGES.rst
index 48cf5be5b..20bbd0dbe 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -53,6 +53,7 @@ Read before updating
 
 #. Red 3.5 comes with breaking changes for cog developers. Look at `Backward incompatible changes in Red 3.5 document <incompatible-changes-3.5>` and `Developer changelog <important-350-2>` for full details.
 #. Fedora 35 and Debian 10 (Buster) are no longer supported as they have already reached their end of life.
+#. On x86-64 systems, we now require that the CPU supports x86-64-v2 instruction set. This roughly translates to us dropping support for x86-64 CPUs that have been released before 2009.
 
 .. _important-350-1:
 
@@ -63,6 +64,7 @@ Breaking Changes
 ****************
 
 - **Core** - The bot will no longer launch without an owner set (:issue:`4926`)
+- **Core - OS support** - On x86-64 systems, we now require that the CPU supports x86-64-v2 instruction set. This roughly translates to us dropping support for x86-64 CPUs that have been released before 2009 (:issue:`6100`)
 
 Additions
 *********
diff --git a/docs/incompatible_changes/3.5.rst b/docs/incompatible_changes/3.5.rst
index bd43fbec4..f268a5dd5 100644
--- a/docs/incompatible_changes/3.5.rst
+++ b/docs/incompatible_changes/3.5.rst
@@ -45,6 +45,15 @@ If you wish to continue using auto-restart functionality, we recommend following
 Behavior changes
 ~~~~~~~~~~~~~~~~
 
+x86-64 CPUs are now only supported if they support x86-64-v2 instruction set
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+On x86-64 systems, we now require that your CPU supports x86-64-v2 instruction set.
+This roughly translates to us dropping support for x86-64 CPUs that have been released before 2009.
+
+This has been mostly dictated by one of our dependencies but some Linux distributions
+are already dropping support for it in their latest versions as well.
+
 Thread-related changes
 ^^^^^^^^^^^^^^^^^^^^^^
 
diff --git a/docs/version_guarantees.rst b/docs/version_guarantees.rst
index 022289d8a..8eb87cb91 100644
--- a/docs/version_guarantees.rst
+++ b/docs/version_guarantees.rst
@@ -38,7 +38,7 @@ their end-of-life date.
     The meaning of architecture names:
 
     - **x86-64** (also known as amd64) refers to computers running a 64-bit version of the operating system
-      on standard Intel and AMD 64-bit processors.
+      on standard Intel and AMD 64-bit processors supporting x86-64-v2 instruction set (post-2008 hardware).
     - **aarch64** (also known as arm64) refers to computers running an ARM 64-bit version of the operating system
       on 64-bit ARM processors (ARMv8-A and ARMv9-A) such as Apple M1 devices or Raspberry Pi computers
       (Raspberry Pi 3B and above, excluding Pi Zero (W/WH) model).