Apple support page on improving Kona Support
Found this on Apple's Support page for improving Kona performance:
Note what they say about updating to 10.5.3 to improve performance on multiple cores.
Also posting the whole thing:
"Final Cut Pro: Improving performance using an AJA Kona card with a Mac Pro
Last Modified: June 05, 2008
If you use an AJA Kona card for video capture and playback with a Mac Pro, there are a number of factors you should consider to enhance performance. The most common issues and solutions are below.
Final Cut Pro
Symmetrical RAM configuration
The Mac Pro comes with two memory riser cards, each with four DIMM slots. With a total of eight slots, you can add up to 16 GB of memory. To achieve optimal performance with memory usage, you should install memory DIMM pairs evenly on both risers. For more details, refer to this article.
PCI Express slot configuration
Mac Pro computers made before 2008 feature four PCI Express (PCIe) expansion slots with 16-lane support and configurable bandwidth. Important: Make sure your PCIe cards are installed in the appropriate slots and that the slots are configured for optimal bandwidth using the Expansion Slot Utility. For details refer to Final Cut Studio: How to optimize PCI Express card performance. AJA also provides information about PCIe slot configurations with Mac Pro at http://www.aja.com/html/support_kona_rec_sys.htm.
Mac Pro (Early 2008) computers and later feature PCIe slots that are automatically configured, so you won't need to use to use the Expansion Slot Utility. Use the following configurations for Mac Pro (Early 2008) computers and later:
If you're using a 4-channel, 8-lane Fibre Channel host bus adaptor card (HBA), it should go into slot 2. The Kona card can go into slot 3 or 4.
If you're using a 2-channel, 4-lane Fibre Channel HBA, it can go into slot 3 or 4, and the Kona card should go into slot 2.
Bounce buffer management
On Mac Pro computers running Mac OS X v10.5 Leopard with more than 2 GB of RAM installed, AJA Kona 3 and AJA Kona LHe cards often require an intermediate "bounce buffer" in memory. The "bounce buffer" combines data from the upper and lower memory addresses, and this buffering can impact performance. You can improve performance by updating to version 5.1 of the AJA Kona software drivers.
Moving process threads between CPU cores
To balance tasks among all the CPU cores, Mac OS X can move process threads to idle CPU cores to improve overall system performance. Though the time it takes to move a thread from one CPU core to another is exceedingly brief, incoming information is held off until the move is complete. Cumulatively, these miniscule delays may affect capture or playback performance. AJA Kona users should update to Mac OS X 10.5.3 for improved performance in this area.
Apple ProRes 422 processing requirements
The Apple ProRes 422 and Apple ProRes 422 HQ codecs reduce storage and bandwidth requirements but require significant processing power, which may impact overall performance.
Note: The AJA Io HD requires much less CPU processing power because the compression is performed by a dedicated hardware processor.
Serial device control and "Tape trouble" messages
When capturing from or outputting to a device using serial control (RS-422), Final Cut Pro regularly queries the device about its current state. If this polling is held off for any reason (such as the other factors listed in this article), Final Cut Pro may display a "Tape trouble" dialog. Updating to the latest Kona drivers and Mac OS v10.5.3 should help resolve this. If polling interruption is still an issue, increasing the polling interval may result in fewer warning dialogs.
To increase the serial device control polling interval, take the following steps:
Use TextEdit (or another plain text editor) and create a new document.
Note: If you are using TextEdit, make sure the document format is plain text (not rich text) by choosing Format > Make Plain Text (or press Shift-Command-T).
Copy and paste the following lines (or type them exactly) into the plain text document:
FileVersion(60243, 41391, 68)
Choose File > Save.
Name the file DisableAltETTPolling.txt and save it in this location:
/Library/Application Support/Final Cut Pro System Support/Plugins
Close Final Cut Pro and reopen it for the change to take effect."