Whether you need to add a third Gigabit Ethernet port to your older Mac Pro for improved performance, or step up to Gigabit Ethernet connectivity for your PC, get a Sonnet Presto Gigabit Pro PCIe Gigabit Ethernet adapter card for PCI Express for an advanced networking solution. This Sonnet card supports link aggregation with your Mac"s onboard Gigabit Ethernet ports and full duplex communication to achieve 2000 Mbps transfer rates - the ideal solution for high-bandwidth data transfer requirements. Presto Gigabit Ethernet Pro PCIe also supports 9000 byte jumbo packet transfers to support higher performance and reduced overhead when transferring large files. Presto Gigabit Pro PCIe is compatible in Mac Pro and PCs with a PCIe slots. This card is also compatible with any Mac with a Thunderbolt port when installed is a Sonnet Echo Express Thunderbolt-to-PCIe card expansion chassis or other qualified Thunderbolt expansion system. Offering simple configuration, this Sonnet card is easy to use, and its support for 1000/100/10BaseT Usage vignette for Presto Gigabit Pro PCIe auto-negotiation and full/half duplex communication enable it to be used in most networks. Presto Gigabit Pro PCIe supports gigabit speeds over common CAT-5 cabling, so costly cable replacement is unnecessary. If your computer already has onboard Gigabit Ethernet, you can add a Presto Gigabit Pro PCIe and use it for dedicated connection to a printer, AirPort Extreme base station, DSL or cable modem, or a video server, while leaving your onboard Gigabit Ethernet port available for other connections.