<p>
  <img class="alignnone size-full" src="images/random-noise.jpg" alt="" width="640" height="480" />
</p>
<p>
  This test generates a pseudorandom noise pattern and copies it to the primary (or back) buffer.<br/>
  Depending on your graphics driver some color depths may be slow.  For example, 15-bit color is slow on the VMWare SVGA3D driver.
</p>