• Overview
  • Tech Specs
  • Performance
  • Videos

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, or Windows® PC, or Linux® computer with PCIe slots; or Thunderbolt™-to-PCIe card expansion system. 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.(1)

Dedicated USB 3.0 5Gb/s Controller Versus Shared Controller

Key Features

Adds SuperSpeed USB Connectivity—Adds four USB 3.0 ports to your Mac Pro tower, or Windows or Linux computer with PCIe slots; 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

Transfer Speed Comparison Test Video

Battery ChargingThe 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.

Thunderbolt LogoOptimized 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 Mac and Windows computers with Thunderbolt ports.

iMac Connected to Echo Express III-D with Allegro Pro USB 3.0 PCIe Card and Connected USB 3.0 Devices

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 or Windows computer 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.

See Tech Specs Tab for footnotes
Part No.  
USB3-PRO-4PM-E Discontinued
Warranty 5-year
Form Factor PCIe computer card
Bus Interface PCI Express 2.0 x4
Peripherals Supported Industry standard USB 3.0, 2.0, and 1.1 peripherals
Bus Powered Peripherals Supported(1) HDs, SSDs, DVDs, and Blu-ray devices up to 2A per port
Cables Supported(2)
  • USB 3.0 with Standard-A male connector
  • USB 2.0 with Standard-A male connector
Chipset (x4) Fresco Logic
RoHS Compliant Yes
Package Contents
  • Allegro Pro USB 3.0 PCIe Computer Card
  • Documentation
USB Support  
Number of Ports 4 external
Standard Complies with OHCI (Open Host Controller Interface), EHCI (Enhanced Host Controller Interface), and xHCI (eXtensible Host Controller Interface) standards
UASP USB attached SCSI protocol supported under
OS X 10.8.5+ and Windows 8.1+
USB Charging USB Battery Charging 1.2 Compliant
(up to 7.5W per port)
Data Transfer Rate 5 Gbps
Chipset Throughput 20 Gbps combined port throughput
Number of Devices Supported Up to 31
Hot Plug Supports hot-pluggable and hot swappable device connection
Boot Support Thunderbolt 3 Macs


Specifications subject to change without notice.





Mac Compatibility

Mac Pro® (3,1 or 4,1 or 5,1)

Not compatible with 2019 Mac Pro

macOS® 10.8.5+

macOS Catalina compatible(3)

Windows Compatibility

Computer with PCIe slots

Windows® 10, 8, 7

Windows Server 2016, 2012, 2008 (64-bit editions)

Linux Compatibility

Computer with PCIe slots

Linux 4.12+ Kernel (LTS version only)

Thunderbolt Compatibility

Mac or Windows PC via a Thunderbolt-to-PCIe Card Expansion System

macOS 10.8.5+

Windows 10 Build 1703 or newer (64-bit)

Technical Notes

  1. See Support Article FAQ 759 for compatible cable types.
  2. USB 3.0 devices require USB 3.0 cables to support USB 3.0 (SuperSpeed) transfer speeds (up to 5 Gb/s). Use of USB 2.0 cables between USB 3.0 devices and Allegro USB 3.0 4-Port is supported, but data transfers are limited to USB 2.0 speeds (up to 480 Mb/s).
  3. Must authorize charging support kernal extension in Security and Privacy System Preferences. (Unlock, then allow.)


Mac OS logoWindows logoPCI Express LogoUSB 3.0 logoRoHS Compliant logo



Transfer Speed Comparison Test Video


Allegro Pro USB 3.0 4-Port PCIe Cards Product Overview (2:30 mins)

View More Sonnet VideosArrow