Final Cut Studio: Optimizing PCI Express card performance

When using Final Cut Studio with a Mac Pro that uses more than one PCI Express (PCIe) card, check that the expansion slots in your Mac Pro are configured to best utilize the bandwidth required by those cards. This can be especially important when working with high definition media or with numerous streams or tracks of media.

The Mac Pro features four full-length PCIe expansion slots with 16-lane mechanical support and configurable bandwidth. Compatible PCIe cards can be installed in these slots, one of which is the graphics card installed in the Mac Pro. Depending on the bandwidth needs of the cards installed in your Mac Pro, the number of lanes provided by each slot can be configured by using the Expansion Slot Utility.

To manage the bandwidth allocated to the cards, Mac OS X includes the Expansion Slot Utility, located in /System/Library/CoreServices. With this utility you can choose different configurations that determine how much bandwidth is allocated to each slot. Choose different configurations to suit various combinations of PCIe cards.

Example 1

If you have added a 2-channel, 4 lane, 2 Gbps Fibre Channel host bus adaptor card (HBA), and a video interface card in addition to your primary graphics card, the configuration that may give you ideal bandwidth allocation across your cards is as follows:
x16 Lane Graphics Slot + Two x4 Lane and One x1 Lane Slots

• The primary graphics card is in Slot 1 (an x16 Lane Slot).
• The 2-channel, 2 Gbps Fibre Channel HBA is in Slot 3 (an x4 Lane Slot).
• The video interface card (for instance AJA or Blackmagic) is in Slot 4 (an x4 Lane Slot).

Example 2

If you have added a 4-channel, 8 lane, 4 Gbps Fibre Channel HBA and a video interface card in addition to your primary graphics card, the configuration that may give you ideal bandwidth allocation across your cards is as follows:
Three x8 Lane + One x1 Lane Slots

• The primary graphics card is in Slot 1 (an x8 Lane Slot).
• The 4-channel, 4 Gbps Fibre Channel HBA is in Slot 2 (an x8 Lane Slot).
• The video interface card (i.e., AJA or Blackmagic) is in Slot 4 (an x8 Lane Slot).