title: WPF slow to start on x64 in .NET Framework 4.0
body: <p>I've noticed that if I build my WPF application for Any CPU/x64, it takes MUCH longer to start (on the order of about 20 seconds) or to load new controls than it does if started on x86 (in release &amp; debug modes, inside or outside of VS). This occurs with even the simplest WPF apps. The problem is discussed in <a href="http://social.msdn.microsoft.com/Forums/en/netfx64bit/thread/476e21c4-6b73-4f8e-bfab-a7aaae5b017f" rel="noreferrer">this MSDN thread</a>, but no answer was provided there. This happens only with .NET 4.0 -- in 3.5 SP1, x64 was just as fast as x86. Interestingly, Microsoft seems to know about this problem since the default for a new WPF project in VS2010 is x86.</p>
  
  <p>Is this a real bug or am I just doing it wrong?</p>
  
  <p><strong>EDIT:</strong> Possibly related to this: <a href="https://stackoverflow.com/questions/2788215/slow-databinding-setup-time-in-c-net-4-0">Slow Databinding setup time in C# .NET 4.0</a>. I'm using data binding heavily.</p>