title: Is it possible to permanently damage the hardware by software?
body: <p>I have just read this question: <a href="https://stackoverflow.com/questions/2740268/could-this-code-damage-my-processor">Could this code damage my processor?</a> and this made me think.</p>
  
  <p>Is it possible to damage hardware just by software? I heard that "in the good old days" (TM), when hard disk actuators were controlled by software, they could be hit against the central spindle, which would damage the drive permanently.</p>
  
  <p>There was also the infamous <a href="http://en.wikipedia.org/wiki/CIH_(computer_virus)" rel="noreferrer">Chernobyl virus</a> which just killed the BIOS and rendered the machine useless, until someone reflashed it.</p>
  
  <p>And there are microcode updates, which can be flashed to the CPU (and I don't know much about them).</p>
  
  <p>But is this still possible today? Could you damage hardware by software? Execute the <code>hcf</code> (Halt &amp; Catch fire) instruction? Grill the cat by increasing WLAN output power?</p>