diff --git a/doc/manual/advanced-topics/distributed-builds.xml b/doc/manual/advanced-topics/distributed-builds.xml
index 1f8d98f5d..f85837003 100644
--- a/doc/manual/advanced-topics/distributed-builds.xml
+++ b/doc/manual/advanced-topics/distributed-builds.xml
@@ -11,9 +11,9 @@ forward Nix builds to other machines over the network.  This allows
 multiple builds to be performed in parallel (thus improving
 performance) and allows Nix to perform multi-platform builds in a
 semi-transparent way.  For instance, if you perform a build for a
-<literal>powerpc-darwin</literal> on an <literal>i686-linux</literal>
+<literal>x86_64-darwin</literal> on an <literal>i686-linux</literal>
 machine, Nix can automatically forward the build to a
-<literal>powerpc-darwin</literal> machine, if available.</para>
+<literal>x86_64-darwin</literal> machine, if available.</para>
 
 <para>You can enable distributed builds by setting the environment
 variable <envar>NIX_BUILD_HOOK</envar> to point to a program that Nix
@@ -30,7 +30,7 @@ variable</link>.</para>
 <example xml:id='ex-remote-systems'><title>Remote machine configuration:
 <filename>remote-systems.conf</filename></title>
 <programlisting>
-nix@mcflurry.labs.cs.uu.nl  powerpc-darwin  /home/nix/.ssh/id_quarterpounder_auto  2
+nix@mcflurry.labs.cs.uu.nl  x86_64-darwin   /home/nix/.ssh/id_quarterpounder_auto  2
 nix@scratchy.labs.cs.uu.nl  i686-linux      /home/nix/.ssh/id_scratchy_auto        8 1 kvm
 nix@itchy.labs.cs.uu.nl     i686-linux      /home/nix/.ssh/id_scratchy_auto        8 2
 nix@poochie.labs.cs.uu.nl   i686-linux      /home/nix/.ssh/id_scratchy_auto        8 2 kvm perf
@@ -59,7 +59,7 @@ bits of information:
   <filename>~/.ssh/config</filename>.</para></listitem>
 
   <listitem><para>A comma-separated list of Nix platform type
-  identifiers, such as <literal>powerpc-darwin</literal>.  It is
+  identifiers, such as <literal>x86_64-darwin</literal>.  It is
   possible for a machine to support multiple platform types, e.g.,
   <literal>i686-linux,x86_64-linux</literal>.</para></listitem>
 
diff --git a/doc/manual/command-ref/conf-file.xml b/doc/manual/command-ref/conf-file.xml
index 4c8f3d9d3..fb7bdf573 100644
--- a/doc/manual/command-ref/conf-file.xml
+++ b/doc/manual/command-ref/conf-file.xml
@@ -430,15 +430,15 @@ flag, e.g. <literal>--option gc-keep-outputs false</literal>.</para>
     <listitem><para>This option specifies the canonical Nix system
     name of the current installation, such as
     <literal>i686-linux</literal> or
-    <literal>powerpc-darwin</literal>.  Nix can only build derivations
+    <literal>x86_64-darwin</literal>.  Nix can only build derivations
     whose <literal>system</literal> attribute equals the value
     specified here.  In general, it never makes sense to modify this
     value from its default, since you can use it to ‘lie’ about the
     platform you are building on (e.g., perform a Mac OS build on a
     Linux machine; the result would obviously be wrong).  It only
     makes sense if the Nix binaries can run on multiple platforms,
-    e.g., ‘universal binaries’ that run on <literal>powerpc-darwin</literal> and
-    <literal>i686-darwin</literal>.</para>
+    e.g., ‘universal binaries’ that run on <literal>x86_64-linux</literal> and
+    <literal>i686-linux</literal>.</para>
 
     <para>It defaults to the canonical Nix system name detected by
     <filename>configure</filename> at build time.</para></listitem>
diff --git a/doc/manual/expressions/builtins.xml b/doc/manual/expressions/builtins.xml
index eae5f5a02..5fd93c831 100644
--- a/doc/manual/expressions/builtins.xml
+++ b/doc/manual/expressions/builtins.xml
@@ -142,7 +142,7 @@ if builtins ? getEnv then builtins.getEnv "PATH" else ""</programlisting>
     evaluates to the Nix platform identifier for the Nix installation
     on which the expression is being evaluated, such as
     <literal>"i686-linux"</literal> or
-    <literal>"powerpc-darwin"</literal>.</para></listitem>
+    <literal>"x86_64-darwin"</literal>.</para></listitem>
 
   </varlistentry>
 
diff --git a/doc/manual/expressions/derivations.xml b/doc/manual/expressions/derivations.xml
index f2a73dccf..5efe2213e 100644
--- a/doc/manual/expressions/derivations.xml
+++ b/doc/manual/expressions/derivations.xml
@@ -16,7 +16,7 @@ of which specify the inputs of the build.</para>
   <listitem xml:id="attr-system"><para>There must be an attribute named
   <varname>system</varname> whose value must be a string specifying a
   Nix platform identifier, such as <literal>"i686-linux"</literal> or
-  <literal>"powerpc-darwin"</literal><footnote><para>To figure out
+  <literal>"x86_64-darwin"</literal><footnote><para>To figure out
   your platform identifier, look at the line <quote>Checking for the
   canonical Nix system name</quote> in the output of Nix's
   <filename>configure</filename> script.</para></footnote> The build