http://blogs.technet.com/yuridiogenes/archive/2008/08/21/why-3gb-can-negatively-affect-your-isa-server.aspx1. Introduction While many Microsoft Application Servers such as Exchange take full advantage of /3GB switch in boot.ini, ISA Server can be seriously affected if you use this switch on it. Before we discuss what this switch does and how can affect ISAen-USCommunityServer 2.1 SP1 (Build: 61025.2)http://blogs.technet.com/yuridiogenes/archive/2008/08/21/why-3gb-can-negatively-affect-your-isa-server.aspx#3109693Thu, 21 Aug 2008 16:18:05 GMTd5e57398-b9ef-4490-9955-07cbb4e4a80d:3109693Thomas Shinder Blog &raquo; Blog Archive &raquo; Beware the /3GB on Your ISA Firewalls<p>PingBack from <a rel="nofollow" target="_new" href="http://blogs.isaserver.org/shinder/2008/08/21/beware-the-3gb-on-your-isa-firewalls/">http://blogs.isaserver.org/shinder/2008/08/21/beware-the-3gb-on-your-isa-firewalls/</a></p> http://blogs.technet.com/yuridiogenes/archive/2008/08/21/why-3gb-can-negatively-affect-your-isa-server.aspx#3223322Tue, 07 Apr 2009 10:02:15 GMTd5e57398-b9ef-4490-9955-07cbb4e4a80d:3223322Forefront TMG (ISA Server) Product Team Blog<p>Short version Does ISA Server benefit from /3GB, PAE or AWE? /3GB: No. While it may help the firewall</p>