Computer Expansion Devices

Allegro Pro USB 3.0 PCIe


Allegro Pro USB 3.0 PCIe

Ultra High-Performance USB 3.0 PCI Express® Adapter Card With 4 Powered Ports

Product Code: SON-USB3PRO-4PME

Product Discontinued

  • Adds SuperSpeed USB Connectivity
    Adds four USB 3.0 ports to your Mac Pro with PCIe slots, Windows PC, or Thunderbolt-to-PCIe card expansion system
  • Four Ports, Four USB 3.0 Controllers
    Supports aggregate transfer speeds of up to 1,800 MB/s (450 MB/s per port)
  • Powers Connected Devices
    Supports USB 3.0 bus-powered hard drives, SSDs, DVDs & Blu-ray devices with up to 2.0A per port
  • Supports Charge & Sync
    Supports USB 3.0 charging port handshake, and will simultaneously sync and charge iPads and other devices that support USB 3.0 charging at 1.5A per device
  • Broad USB 3.0 Device Support & Compatibility
    Supports storage, hubs, and other USB-IF compliant USB 3.0 devices; compatible with USB 2.0 devices
  • Supports Hot-Swappable Device Connection
    Plug in and disconnect peripherals without shutting off your computer
  • Optimized for Thunderbolt
    Provides optimum performance over Thunderbolt
  • Easy Installation
    Quick and easy user installation into any available PCIe slot

Mac Compatibility

  • Mac Pro® (with card slots)
  • OS X® 10.8.5+
  • macOS Sierra compatible

PC Compatibility

  • PC Desktop (with PCIe slots, PCIe 2.0 slots recommended)
  • Windows® 10, 8, 7
  • Windows Server 2016, 2012, 2008


All new Sonnet Products purchased on or after January 1, 2019, have a Two Year Limited Warranty, except as listed here. All new Sonnet Products purchased on or before December 31, 2018, have a One Year Limited Warranty, except as listed here.

Add Four Powerful 5Gb/s SuperSpeed USB 3.0 Ports—Each with its Own Dedicated Controller
Do you frequently need to hook up multiple USB 3.0 drives for fast backups and drive-to-drive duplication? If you are looking for the best possible performance, install the Allegro™ Pro USB 3.0 PCIe adapter in your Mac Pro® tower, Windows® PC, or Thunderbolt™ 2-to-PCIe card expansion system.

4 Independent Controllers!

This pro Sonnet card adds four SuperSpeed USB 3.0 ports to your computer, but unlike conventional adapter cards, each port has its own controller. Instead of sharing a single controller’s bandwidth, each port gets its own, enabling the Allegro Pro card to support aggregate transfer speeds of up to 1,800 MB/s (450 MB/s per port)!

The Allegro Pro USB 3.0 PCIe card features a PCIe 2.0 x4 bus interface to take advantage of one of your computer’s fast expansion card slots. This card installs easily into any x4 PCI Express® (PCIe) slot that supports a full-height card, features hot-pluggable and hot-swappable device connection support with automatic device configuration, and works with all USB-IF compliant USB 3.0 and USB 2.0 peripherals.(see FAQs)

The Power to Charge and Sync
Sonnet specially engineered the Allegro Pro card to provide extra power through its ports without the need for you to connect an auxiliary power cable. Delivering up to 10W of power per port, this Sonnet solution supports USB 3.0 bus-powered hard drives, SSDs, DVDs & Blu-ray™ devices without the need to connect an additional AC power adapter. The Allegro also supports the USB 3.0 charging specification that enables you to simultaneously charge and sync your iPad®, iPhone®, or other device that supports USB 3.0 charging.

Optimized for Thunderbolt
Got a Thunderbolt connection, but no PCIe slot? This card is ideal for use in one of Sonnet’s Echo Express™ or xMac™ Thunderbolt 2-to-PCIe Card Expansion Systems—the combo enables you to add four SuperSpeed USB 3.0 ports to iMac®, Mac® mini, new Mac Pro®, MacBook Air®, and MacBook Pro® computers with Thunderbolt ports.

Why limit performance by connecting multiple storage devices to your Mac’s built-in USB 3.0 ports? Install the Allegro Pro card into an Echo Express III-D (or other Thunderbolt-to-PCIe card expansion system) and connect it to your Mac via Thunderbolt cable—you’ll add four USB 3.0 ports, each with a dedicated controller, for faster data transfers from media card readers, storage, and other peripherals.

When connected to the Allegro Pro USB 3.0 PCIe, Allegro USB 3.0 4-Port PCIe, Tango 3.0 PCIe, or Tempo Duo PCIe card, my bus-powered USB 2.0 or 3.0 drive or SSD will not reliably mount or transfer data.

High power bus-powered drives are supported only by the Allegro Pro USB 3.0 PCIe (USB3-PRO-4PM-E), Allegro USB 3.0 4-Port PCIe (USB3-4PM-E), and Tango 3.0 PCIe (FW8USB3A-E) cards, but not the discontinued USB 3.0 PCIe cards (USB3-E or USB3M-E), the initial version of the Tango 3.0 PCIe card (FWUSB3-E), nor any USB 2.0 cards.

If you are still having trouble, this may be a problem due to a voltage drop in the USB cable. Use the following guide to select the correct cable for your application. 

In general, these cables should work with SSDs or optical drives drawing up to 2A of current:

Type........Power-Carrying Wires....Cable Outside Diameter....Maximum Cable Length

USB 2.0..........28 AWG...............................3.8mm...........................0.15m (0.5 ft)

USB 2.0..........24 AWG...............................4.7mm...........................0.3m ( 1 ft)

USB 2.0..........20 AWG...............................5.0mm..............................1m ( 3 ft)

USB 3.0..........22 AWG...............................6.0mm..............................1m ( 3 ft)

Generally, the gauge of the power-carrying wires can be inferred from the cable outside diameter.

Sonnet - macOS High Sierra Compatibility Information

Sonnet is currently testing product compatibility for macOS 10.13 (High Sierra). The following are compatible:

  • Allegro Pro USB 3.0 4-Port PCIe Computer Card
  • Documentation

Also Consider

Sonnet Echo Express III-D
Sonnet Echo Express III-D

Desktop 3-slot Thunderbolt 2 Expansion Chassis for PCIe cards

Sonnet Echo Express SE II
Sonnet Echo Express SE II

2-slot Thunderbolt 2 Expansion Chassis for PCIe cards

Sonnet xMac Pro Server
Sonnet xMac Pro Server

Mac Pro PCIe 2.0 expansion system and 4U rackmount enclosure


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