diff --git a/en_US.ISO8859-1/books/faq/book.sgml b/en_US.ISO8859-1/books/faq/book.sgml
index 11bd412f61..1e93ee2221 100644
--- a/en_US.ISO8859-1/books/faq/book.sgml
+++ b/en_US.ISO8859-1/books/faq/book.sgml
@@ -2106,6 +2106,69 @@
     </qandaset>
       </sect1>
 
+    <sect1 id="compatibility-memory">
+      <title>Memory</title>
+
+      <qandaset>
+	<qandaentry>
+          <question id="memory-upper-limitation">
+            <para>Does &os; support more than 4&nbsp;GB of memory (RAM)? More
+              than 16&nbsp;GB? More than 48 GB?</para>
+          </question>
+
+          <answer>
+            <para>Yes. &os; as an operating system generally supports as much
+	      physical memory (RAM) as the platform it is running on does. Keep in
+	      mind that different platforms have different limits for memory;
+	      for example &i386; without <acronym>PAE</acronym> supports
+	      at most 4&nbsp;GB of memory
+	      (and usually less than that because of PCI address space) and
+	      &i386; with PAE supports at most 64&nbsp;GB memory.
+	      AMD64 platforms currently deployed support up to
+	      1&nbsp;TB of physical memory.</para>
+          </answer>
+	</qandaentry>
+
+	<qandaentry>
+          <question id="memory-i386-over-4gb">
+            <para>Why does &os; report less than 4&nbsp;GB memory when installed
+              on an &i386; machine?</para>
+          </question>
+
+          <answer>
+            <para>The total address space on &i386; machines is 32-bit, meaning that at
+	      most 4&nbsp;GB of memory is addressable (can be accessed). Furthermore,
+	      some addresses in this range are reserved by hardware for different purposes,
+	      for example for using and controlling PCI devices, for accessing
+	      video memory, and so on.  Therefore, the total amount of memory usable by the
+	      operating system for its kernel and applications is limited to significantly
+	      less than 4&nbsp;GB. Usually, 3.2&nbsp;GB to 3.7&nbsp;GB is the maximum usable
+	      physical memory in this configuration.</para>
+
+            <para>To access more than 3.2&nbsp;GB to 3.7&nbsp;GB of installed memory (meaning
+	      up to 4&nbsp;GB but also more than 4&nbsp;GB), a special tweak called
+	      <acronym>PAE</acronym>
+	      must be used. PAE stands for Physical Address Extension and is a
+	      way for 32-bit x86 CPUs to address more than 4&nbsp;GB of memory. It
+	      remaps the memory that would otherwise be overlayed by address
+	      reservations for hardware devices above the 4&nbsp;GB range and uses it
+	      as additional physical memory (see &man.pae.4;). Using PAE has
+	      some drawbacks; this mode of memory access is a little bit slower
+	      than the normal (without PAE) mode and loadable modules
+	      (see &man.kld.4;) are not supported.  This means all drivers must
+	      be compiled into the kernel.</para>
+
+            <para>PAE is not much used nowadays because most new x86 hardware also
+	      supports running in 64-bit mode, known as AMD64 or
+	      &intel;&nbsp;64.  It has a much larger
+	      address space and does not need such tweaks. &os; supports AMD64
+	      and it is recommended that this version of &os; be used instead
+	      of the &i386; version if 4&nbsp;GB or more memory is required.</para>
+          </answer>
+	</qandaentry>
+      </qandaset>
+    </sect1>
+
       <sect1 id="compatibility-processors">
 	<title>Architectures and processors</title>