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.

• Provide enough space at each end of the computer for unrestricted airflow into the base and out the exhaust at the top. Make sure that the air intake and exhaust ports are not covered.
• When using multiple Mac Pro (Late 2013) computers, do not direct the exhaust at the top of one Mac Pro towards the intake of another system. Place the computers side by side with a gap of at least several inches between them.
• When on its side, secure the Mac Pro (Late 2013) to be sure that it doesn't roll. Place the computer on a protective surface that will not scratch or damage the enclosure. Note: The Apple Limited Warranty does not cover cosmetic damage to the enclosure.
• Orient the computer so that the Input/Output (I/O) panel remains accessible during use.

General

The Mac Pro (Late 2013) has four memory slots that you can upgrade with up to 64GB of memory using 1866 MHz DDR3 ECC compliant memory DIMMs. To ensure compatibility, Apple recommends that you use Apple-approved memory. You can purchase Apple-approved memory online from the Apple Store or by visiting an Apple Retail store or Apple Authorized Reseller.

Requirements

When you upgrade the memory in your Mac Pro (Late 2013) it must meet these requirements.

• 1866 MHz DDR3 full length DIMM. Mixing memory speeds is not recommended.
• Error-correcting code (ECC).
  
• 4GB, 8GB, or 16 GB DIMMs.
• Unbuffered (UDIMM) or Registered (RDIMM). Do not mix UDIMMs and RDIMMs.
  
• 240 pin DIMM.
• 1.5 or 1.35 volts.
  
• Use the same size memory modules across all slots to maximize performance.
• DIMMs with heatsinks are not supported and may damage the DIMM mechanism.

Important: All DIMMs must be 1866MHz DDR3 ECC compliant. The Mac Pro supports both unbuffered UDIMMs and registered RDIMMs, but it is important not to mix these two types of memory. Mixing UDIMMs and RDIMMs will result in a memory error tone when you turn on your computer.

Recommended configurations

Refer to Mac Pro (Late 2013): Installing or replacing memory for step by step memory installation instructions.

Choose Compressor > Preferences (or press Command-comma) and click Advanced. Place a checkmark next to “Enable additional Compressor instances.” Then, choose a number of instances from the pop-up menu.

Compressor changes the number of additional instances available in the pop-up based on the capabilities of your computer to optimize performance. In some cases the “Enable additional Compressor instances” checkbox may be grayed out. This is expected if Compressor will not allow for additional instances of Compressor to be enabled.

Compressor checks the number of cores and the amount of memory you have and allows you to create one additional instance for every four cores and 2GB of memory (above the 2 GB minimum requirement). The following table shows the number of additional instances you can configure for different numbers of cores and available memory.  

Note: These are additional instances of Compressor. There is always one instance running when “Allow other computers to process batches on my computer” is turned on, even if Compressor is not open.

For more information, refer to Enable one or more instances of Compressor in Compressor Help.

MacBook Pro (Retina, Late 2013) and Mac Pro (Late 2013) computers can use 4K Ultra HD TVs with OS X or Windows (using Boot Camp). 4K Ultra HD TVs using these specifications are supported via the HDMI port:

• 3840-by-2160 resolution at 30Hz
• 4096-by-2160 resolution at 24Hz (mirroring is not supported at this resolution)

Ports and configurations for 4K Ultra HD TVs

With the MacBook Pro (Retina, Late 2013), you can connect:

• One 4K Ultra HD TV to the HDMI port and one Thunderbolt or third-party (non-4K) display via Thunderbolt.

With the Mac Pro (Late 2013), you can connect:

• Two 4K Ultra HD TVs¹ and up to two 4K displays via Thunderbolt.


¹You can use the HDMI port for one of these and a Mini DisplayPort to high-speed HDMI adapter for the other. If you do, don't plug the second Ultra HD TV into the bottom two Thunderbolt ports on the Mac Pro since they are on the same bus as the HDMI port. Mac Pro (Late 2013): Using multiple displays explains in more detail how to use the different Thunderbolt configurations on the Mac Pro (Late 2013).

The Mac Pro (Late 2013) features two distinct audio ports.

Audio out: The left audio port with a speaker icon is a 1/8" stereo minijack for audio line out. It can use analog audio and digital S/PDIF fibre optic cables. Audio devices you connect to the port will appear in System Preferences > Sound > Output. Note that this port does not support headsets or microphones.

Headphone port: The right audio port with a headset icon is a 1/8" stereo minijack for headphones. When you plug in headphones to this port, sound is redirected from the internal speakers to the headphones. Headphones will appear in System Preferences > Sound > Output. If the headset contains a microphone, it will appear in System Preferences > Sound > Input. iPhone headsets including mic and inline controls are supported. Digital output devices are not supported on this port.

All the ports and connectors shown here are located on the Input/Output (I/O) panel.

Audio line out (digital/analog) minijack 
The audio line out port is a 1/8" minijack that supports stereo analog audio and digital S/PDIF fiber optic cables. You can find audio devices you connect to this port in System Preferences > Sound > Output. This port does not support headsets or microphones.

Headphone minijack
The headphone out port is a 1/8" minijack that supports headphones and headsets. When you plug in headphones to this port, sound is redirected from the internal speakers to the headphones. Headphones will appear in System Preferences > Sound > Output. If the headset has a microphone, it will appear in System Preferences > Sound > Input. iPhone headsets including mic and inline controls are supported. Digital output devices are not supported on this port.

Enclosure latch
This latches the enclosure to the system core. Keep the system latched during normal use. The enclosure must be on for you to be able to turn on the computer.

USB 3 ports (4)
There are a total of four USB 3 ports. You can connect USB 3, USB 2, and USB 1.1 devices to these ports.

The USB ports use USB Type A connectors which have four pins each. USB 3 (also known as "SuperSpeed USB") can transfer data up to 5Gbps. USB 3 devices can use up to 900mA of power (compared to USB 2 device which can use up to 500mA). Use USB 3 cables to take advantage of this functionality. For complete information on using USB 3 devices, see Using USB 3 devices on Mac computers FAQ.

Thunderbolt 2 ports (6)
Thunderbolt is a revolutionary I/O technology that supports high-resolution displays and high-performance data devices through a single, compact port.

The Mac Pro (Late 2013) features six Thunderbolt 2 ports connected using three independent Thunderbolt 2 controllers. Each port supports up to 20Gb/s of data throughput using channel bonding. Thunderbolt supports up to six devices per port for a total of up to 36 devices connected to your Mac Pro.

Thunderbolt 2 is backward and forward compatible with Thunderbolt devices, allowing Thunderbolt devices to connect to Thunderbolt 2 ports and Thunderbolt 2 devices to be connected to Thunderbolt ports at Thunderbolt speeds.

Mac Pro (Late 2013) Thunderbolt ports support the following technologies as well.

• Mini DisplayPort output using a Mini DisplayPort to Mini DisplayPort cable.
• DVI output using a Mini DisplayPort to DVI Adapter.
• VGA output using a Mini DisplayPort to VGA Adapter.
• Dual-Link DVI output using Mini DisplayPort to Dual-Link DVI Adapter. This supports the 30-inch Apple Cinema HD Display.
• HDMI audio and video output using a third-party Mini DisplayPort to HDMI Adapter.

Gigabit Ethernet ports (2) 
There are two built-in 10/100/1000 Gigabit Ethernet ports. You can use these to connect an Ethernet cable from a cable or DSL modem, hub, switch, or router, or to connect to another Mac computer. The Ethernet port also supports jumbo frames. The connected device can be a 10Base-T, 100Base-TX, or a 1000Base-T device, and the port automatically detects which type of device is connected. You don't have to use an Ethernet crossover cable to connect to other Ethernet devices.

HDMI port
Use the HDMI port to connect a compatible HDMI display, TV, or projector. Mac Pro supports HDMI 1.4 to enable connections to UltraHD and 4K displays. The HDMI port supports the following resolutions.

• 1080p resolution at up to 60Hz
• 3840-by-2160 resolution at 30Hz
• 4096-by-2160 resolution at 24Hz

What display configurations can I use with my Mac Pro (Late 2013)?

You can connect up to six displays to your Mac Pro (Late 2013) running Windows 8 via Boot Camp. Check the list below to be sure you're setting up your displays in a supported configuration via the HDMI and Thunderbolt ports.

You can connect:

• Six Apple LED Cinema Displays (27-inch) or third-party displays via Thunderbolt. For best results, attach displays to different Thunderbolt busses when possible (see figure below).
• Three Apple Thunderbolt Displays (27-inch). Connect only one per Thunderbolt bus (see figure below). Note: You could connect three more LED Cinema Displays (27-inch) or third-party displays, one per Thunderbolt bus, for a total of six displays.
• Two Apple Thunderbolt Displays (on Thunderbolt bus 1 and 2) and one 4K Ultra HD TV using HDMI.
• Two 4K displays (on Thunderbolt buses 1 and 2) and one 4K Ultra HD TV on HDMI).

Which 4K displays can I use?

You can use the Sharp PN-K321 and the ASUS PQ321Q with the Mac Pro (Late 2013). These displays require using a Mini DisplayPort to DisplayPort cable or a High-Speed HDMI cable to connect to your Mac Pro.

Notes:

• European versions of these displays do not have an HDMI port. 
• Some Windows 8 applications might display only half of the screen on a 4K display when using 60Hz. Change the 4K settings on the display using the display's built-in controls to 30Hz to display a full screen when using these applications.

Can I connect DVI displays?

Yes, with an appropriate adapter. Use two or fewer DVI displays (or other TMDS signaling devices) with your Mac Pro at the same time. Use only one if you are also using an HDMI device.

Where can I find more information on connecting displays to my Mac Pro (Late 2013)?

• Using 4K Ultra HD TVs with the Mac Pro (Late 2013)
• Using multiple displays on a Mac Pro (Late 2013) with Mac OS X