Operating System Requirements: Mac OS X 10.5+ Description: This software enables the use of all versions of the Tempo SATA E2P, Tempo SATA Edge ExpressCard/34 and Tempo SATA ExpressCard/34 host controllers running Mac OS X version 10.5.8-macOS 10.12.6. This version has been updated to be Thunderbolt technology-aware. This driver does not support macOS 10.13 and newer.
Spread Spectrum Clocking is a way to lower electromagnetic interference or EMI. This is important for storage solutions that are required to pass FCC and other agency certifications. All current Serial ATA disk drives implement SSC (some allow you to turn this feature on/off). However, some older SATA drives do not implement SSC. All Sonnet Serial ATA host adapter cards support SSC but will also work with disk drives that do not.
Unfortunately, not. The driver was written by the 3Gb SATA controller chip maker, Silicon Image, and they no longer maintain the macOS driver for this chip.