title: Virtualbox says VT-x is not available (VERR_VMX_NO_VMX). What is VT-x?
body: <pre><code>Failed to open a session for the virtual machine Samsung Galaxy S6 - 6.0.0 -     API 23 - 1440x2560.
  
  VT-x is not available (VERR_VMX_NO_VMX).
  
  Result Code: E_FAIL (0x80004005)
  Component: ConsoleWrap
  Interface: IConsole {872da645-4a9b-1727-bee2-5585105b9eed}
  </code></pre>
  
  <p>What is this <code>VT-x</code> and why is it needed ?</p>
  
  <p>Also I can create a VM and install Linux but why can't I start any Android device on VirtualBox ?</p>
  
  <p>I have genymotion successfully installed but every time I run device it gives me above error. </p>
  
  <p>Any idea how to solve this issue ? </p>