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Add More USB Connections Without Compromise

Peripherals connected to Sonnet USB adapter cardEverybody's got USB 2.0 peripherals— keyboards, mice, printers, scanners, joysticks, digital cameras, external drives, and devices—and there never seems to be enough ports on a computer to plug all of them in at the same time. Problem solved—install a Sonnet Allegro™ USB PCIe in your computer to add five more USB 2.0 ports. Considering a hub? Consider the tradeoffs. Every peripheral you plug in has to share a single port's bandwidth (potentially affecting the devices' performance), and you may have to plug it into a power outlet as well as your computer in order to operate some devices.

Allegro USB PCIe USB ports diagram

Key Features

Adds five USB 2.0 ports to any compatible computer without the tradeoffs of a hub

Supports hot-swappable device connection—plug in and disconnect peripherals without shutting off your computer

Supports bus-powered devices without a separate power supply

Easy installation—plug and play—no drivers to install


Sonnet's Allegro USB PCIe adds five (four external, one internal) high-speed USB 2.0 connections to your computer without the need for an external box or AC power adapter—no trade-offs necessary. This Sonnet adapter features hot-pluggable and hot-swappable device connection support with automatic device configuration, so you can plug in and disconnect devices without having to shut down your computer. Each of Allegro USB PCIe’s five powered ports supports bus-powered peripherals (devices that work without a separate power supply, including some small external drives and scanners) and hi-speed data transmission. With no drivers to install, this card offers simple plug and play installation in Mac and Windows computers. Allegro USB PCIe adds more USB 2.0 connectivity to your computer, outside and in, without compromise.

See Tech Specs Tab for footnotes
Part No.  
USB2-E Discontinued
Warranty 1-year
Form Factor PCIe computer card
Bus Interface PCI Express x1
Number of Ports
  • 4 external USB 2.0
  • 1 internal USB 2.0
RoHS Compliant Yes
Package Contents
  • Allegro USB PCIe Computer Card
  • Documentation
USB Support  
Standard USB Specification v. 2.0/1.1/1.0 compatible. Complies with OHCI (Open Host Controller Interface) and EHCI (Enhanced Host Controller Interface)
Cables Supported USB 2.0 with Standard-A male connector
Peripherals Supported Supports all industry standard USB 2.0 and USB 1.1 peripherals
Data Transfer Rate 480/12 Mbits/s
Number of Devices Supported Up to 127
Hot Plug Supports hot-pluggable and hot-swappable device connection


Specifications subject to change without notice.





Mac Compatibility

Mac Pro® (with card slots)

Power Mac® G5 (with PCIe slots)

OS X® 10.3 - 10.10.5(1)

Windows Compatibility

PC desktop (with PCIe slots)

Windows® 10, 8, 7, Vista®, XP (SP2)

Technical Notes

  1. Deep Sleep not supported under OS X 10.4 or 10.3.


Mac OS logoWindows logo FireWire Logo PCI Express logo RoHS Compliant logo




YouTube product review

Geekanoids Review: Allegro USB PCIe

Note: U.S. price mentioned in video is incorrectly stated

Buzzillions Finalist 2011

Very Reliable
This is my second Sonnet PCIe card and both have performed flawlessly. I have an existing FW/USB card and I've recently added this USB card for more expandability and they both have worked perfectly.

I have the cards installed in a Mac Pro (Early 2008). They install fairly easily, require no drivers and are well-built. A bit more expensive than other options out there but worth it if you want professional build and reliability."

Buzzillions Finalist 2011

Effortless Install in My Mac Pro
I had to do a little research to find out which brand would work on my (4-year-old) Mac Pro desktop computer.

All the good reviews pointed to this product and the inquiries paid off. Product installed effortlessly and worked without a glitch.

I would recommend this product to anyone wanting to fill one of the empty slots on a Mac Pro, when (as it did to me) it just does not make sense to deal with hubs and wires on the desktop.

So, FWIW you can buy this product with confidence IMHO."

Buzzillions Finalist 2011

Better Than Competition
I ordered a less expensive card and it didn't fit in my Mac Pro. The Sonnet card fix exactly. It works better than the original USB controller in the Mac Pro."

Awards & Case Studies
Quote bubbleSee what reviewers and customers have to say about other Sonnet products in our News section under Product Reviews and Case Studies.