| A computer's ExpressCard/34 slot supports two bus standards, PCIe and USB 2.0. ExpressCard adapters fall into two basic categories: those that use the ExpressCard's PCIe interface, and those that use its USB 2.0 interface. Upon inserting the ExpressCard card, the computer automatically senses which interface the adapter is using. Examples of PCIe-based adapters include the cards listed in the Compatible ExpressCard/34 Adapters FAQ. Examples of USB 2.0-based adapters include USB 2.0 cards and many multi-format memory card readers such as Sonnet's 21-in-1 Multimedia Memory Card Reader & Writer.
Thunderbolt technology natively supports the PCIe bus standard, but not USB 2.0, so the Echo ExpressCard/34 Thunderbolt Adapter only interfaces with PCIe-based ExpressCard/34 adapters. As a result, all USB 2.0-based ExpressCard/34 cards are unsupported. |