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.
Failure to power off a Tempo card before ejecting it may have an unpredictable result for OS X.
You should follow these steps:
1. Unmount any drives attached to the Tempo card by dragging them to the Eject icon in the dock.
2. Click the Card's icon in the menu bar and select "Power Off Card" from the drop down menu.
3. Push and release the Tempo card to eject.