I assume the Sonyt has a built-in USB hub, so you would need a USB PCI card, and you must be running at least MacOS 8.5.1 (which requires the USB Adapter Card Support software), in addition you MAY need a specific manufacturer's driver for the USB card (some are supported by the card support extensions without additional drivers, but YMMV) The USB support software version to use varies with different OS versions, and if you have MacOS 9.1, the support software is already included, and separate drivers may not be needed at all! Of course, you only have 2 slots, and if both are taken, no good news about that. (The available USB-SCSI adapters (hooking a SCSI device to a USB port) would work in the wrong direction for you, SCSI-USB has not been done to my knowledge).