NewerTech MAXPower USB/eSATA 2x2 Host Adapter For Macs and PCs Designed specifically for OS X 10.8.3 and later, compatible with Windows 7, Windows 8, and later Compatible with Mac Model IDs: MacPro3,1 | MacPro4,1 | MacPro5,1 | Xserve3,1. Also compatible with OWC Mercury Helios Thunderbolt PCIe expansion chassis PCI Express 2.0 x4, USB 3.0 ports x2, 6Gb/s eSATA ports x2 Compliant with xHCI Specification v1.00 Thunderbolt Technology Enabled eSATA Hot-Swap and Hot-Plug PCI Express 2.0 x4 Two USB 3.0 ports with Type A connectors (female) Two 6Gb/s eSATA Ports 20Gb/s transfer bandwidth Dedicated per-port performance architecture Optimized for all USB 3.0 &amp; eSATA 6G/s storage devices Thunderbolt compatible Backwards compatible with USB 2.0 &amp; 1.1, and eSATA 3Gb/s eSATA Hot-Swap and Hot-Plug Compliant with xHCI (Extensible Host Controller Interface) Specification v1.00 Thunderbolt Technology Enabled Mac Pro (Early 2008)<span class="a-text-bold">Model ID:</span>MacPro3,1(2.8GHz, 3.0GHz, 3.2GHz) Mac Pro (Early 2009 Quad-Core)<span class="a-text-bold">Model ID:</span>MacPro4,1(2.66GHz, 2.93GHz, 3.33GHz) Mac Pro (Mid 2010 Quad-Core)<span class="a-text-bold">Model ID:</span>MacPro5,1(2.8GHz, 3.2GHz, 3.33GHz) Mac Pro 6-Core(Mid 2010-2012)<span class="a-text-bold">Model ID:</span>MacPro5,1(3.33GHz) Mac Pro 8-Core (Mid 2010)<span class="a-text-bold">Model ID:</span>MacPro5,1(2.4GHz) Mac Pro 12-Core(Mid 2010-2012)<span class="a-text-bold">Model ID:</span>MacPro5,1(2.40GHz, 2.66GHz, 2.93GHz, 3.06GHz) Xserve Quad-Core (Early 2009)<span class="a-text-bold">Model ID:</span>Xserve3,1 (2.26GHz) Xserve 8-Core (Early 2009)<span class="a-text-bold">Model ID:</span>Xserve3,1(2.26GHz, 2.66GHz, 2.93GHz) OWC Mercury HeliosThunderbolt PCIeexpansion chassis PCs compatible with the specifications listed. MXPCIE2E2U3 Intel-based Mac with available PCI Express 2.0 x4 lane slot <span class="a-text-italic">Backwards comaptible with PCI Express 1.0a at reduced speeds</span>* Full-height, half-length Mac OS X 10.8.3 and later Windows 7, Windows 8** and later <ul class="a-unordered-list a-vertical"> For Windows 7, a driver is required for proper installation of the USB ports. USB 3.0: up to 500MB/s per port eSATA: up to 500MB/s per port Up to 20Gb/s total card bandwidth.<br> <span class="a-text-italic">Dedicated per port performance architecture fully utilizes the PCIe 2.0 x4 bandwidth</span> Via USB 3.0: No Via eSATA: No Via USB 3.0: No Via eSATA: No x2 USB 3.0 Type A ports x2 eSATA 6Gb/s ports none Supports all USB communication speed data rate of Low-speed (1.5 Mbps) / Full-speed (12 Mbps) / High-speed (480 Mbps) / SuperSpeed (5Gbps) Supports all USB compliant data transfer type as follows; Control / Bulk / Interrupt Compliant with Intel&#039;s USB3.0 Host Controller Interface (xHCI) Specification revision 1.00 UAS (USB Attached SCSI) enabled for multiple simultaneous data transfer requests Compatible with both USB 3.0 &amp; USB 2.0 hubs Compliant with Serial ATA Specification 3.0 Supports all SATA communication speed data rate of 6.0 Gb/s, 3.0 Gb/s, 1.5 Gb/s Supports AHCI 1.0 Supports Native Command Queuing (NCQ) Yes Yes Yes, may be used in externalThunderbolt expansion chassis In Mac OS X, you may experience disk ejections when waking from sleep. It is a known issue for add on PCIe cards used with Mac OS X. This issue is not present with Windows 7 or 8 operating systems. It is suggested that you manually eject USB 3.0 devices prior to putting your Mac to sleep. eSATA ports do not support port multiplication Bootcamp Compatibility: this card is not compatible with MacPro3,1 models that have both an OS X startup volume and a Windows Boot Camp startup volume installed. The computer will fail to boot either OS in this scenario. 4.72&#034; x 4.53&#034; x 0.75&#034; (12.0 x 11.5 x 1.9 cm) 0.43 lbs (0.19kg)