Mac Pro 2013 can also be used in horizontal position

  Although Mac Pro 2013 was promoted by Apple Lossless Audio CODEC (ALAC), as a product that can only be used when it is in a vertical position, probably few will be surprised to learn that it also works in a horizontal position. In a support document published by the company Apple Lossless Audio CODEC (ALAC),, the Americans claim that users can place the new Mac Pro in a horizontal position and use it without problems as long as they ensure that the hard drive system is not blocked. More details are available in this page.

Although the Mac Pro (Late 2013) is designed to operate in an upright position, you can also use it on its side.

The Mac Pro (2013) has a fan system capable of cooling the computer in a vertical or horizontal orientation as long as you follow these guidelines.