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Mac Pro Tower, Windows PC, and Thunderbolt Expansion System
Install up to Four M.2 NVMe SSDs into a
PCIe Card Slot

x16 PCIe SlotHigh-speed Data Transfers

If you need to add internal storage to your computer setup and high-speed data transfers are critical to your work, don’t look to 2.5" SATA SSDs—you need an NVMe SSD-based upgrade. Today’s NVMe PCIe SSDs offer tremendous performance, easily outclassing 2.5" SATA SSDs. Sonnet’s M.2 4x4 PCIe card enables you to mount four M.2 NVMe PCIe SSDs(1) onto a single x16 card slot—it can transform the way you work.

With the Sonnet M.2 4x4 PCIe card installed in your 2019 Mac Pro® or older Mac Pro tower; Windows® or Linux® PC desktop or server; or Thunderbolt™ to PCIe card expansion system with an available x16 PCIe slot, you can use it for instant-access media storage or as a high-performance scratch disk. Mac® users can even install macOS® on one SSD to create an incredibly fast boot drive(2) and create a RAID 0 set with the other installed SSDs without loss of performance. However you use it, this card’s performance is impressive.

Sonnet M.2 4x4 PCIe Card



Performance Oriented

Sonnet’s M.2 4x4 PCIe card is a full-height, full-length PCIe 3.0 card with a 16-lane (x16) interface. Featuring a unique Sonnet-designed x16 PCIe bridge, the card devotes four lanes of PCIe 3.0 bandwidth to each SSD you install. When installed in a Windows PC’s PCIe 3.0 slot with four SSDs formatted in a RAID 0 configuration, the card is capable of 8,500 MB/s transfers. Aggregate transfer speeds from four non-RAIDed SSDs of up to 12,000 MB/s are possible! 

Four Lanes of PCIe 3.0 Bandwidth

Key Features

Adds Ultra-Fast SSDs to Your System—Mounts four M.2 NVME SSDs (sold separately) in your computer’s, or Thunderbolt expansion chassis' x16 PCIe slot

High-Performance PCIe Interface—PCI Express 3.0 x16 host bus interface for high-performance applications

Superior Performance—Concurrent data transfers speeds up to 12,000 MB/sec(3)

Great Way to Add Up to 8TB of M.2 SSD Storage to Computers with Thunderbolt—Perfect for use in Sonnet's Echo™ Express III-D, Echo Express III-R, xMac™ mini Server, xMac Pro Server, and Thunderbolt expansion systems

RAID Support—Supports macOS and Windows RAID 0; macOS supports RAID 5 with the addition of SoftRAID

macOS Boot Support—Supports booting from a single (non-RAIDed) attached SSD

Concatenation (Span) Support—Supports creating a single, large volume that spans all four SSDs under Mac, Windows, or Linux

NVMe Compliant SSDs—Typically no drivers required(4)

S.M.A.R.T. Support—Supports S.M.A.R.T. data reporting

Smart Fan—The fan is temperature-controlled and spins only when and as fast as needed, minimizing audible noise

Lifetime Technical Support

Mac Pro RAID 0 Performance

Install the M.2 4x4 PCIe card with your SSDs into your 2010 or 2012 Mac Pro tower to obtain performance you never thought possible. Planning to upgrade to a 2019 Mac Pro? Move the Sonnet card to it and see even greater performance!

2019 Mac Pro

2019 Mac Pro RAID 0 Performance Chart

2010/2012 Mac Pro

2010/2012 Mac Pro RAID 0 Performance Chart

Performance based on ATTO Disk Benchmark (available on the Apple® App Store) with Samsung 970 EVO Plus 1TB SSDs with 64MB transfer size. See our M.2 4x4 Performance PDF for additional benchmarks and details.

iMac with Echo Express III-DNo Slowdowns

Sonnet designed the M.2 4x4 PCIe Card with a custom cooling solution incorporating several components. These include a heatsink, and a smart fan that is temperature-controlled and spins only when and as fast as needed to minimize audible noise. Together, they enable your SSDs to operate for sustained periods—most importantly during large file transfers—without thermal throttling of the SSDs’ performance, a problem encountered by competing products.

Thunderbolt Port? Connect Four SSDs Through One Cable

Got a Thunderbolt connection, but no PCIe card slot? Sonnet’s M.2 4x4 PCIe card is ideal for use in one of our Echo™ Express III-D, III-R, or xMac™ Thunderbolt to PCIe card expansion systems—the combo enables you to add up to four SSDs to any Mac or Linux computer with Thunderbolt 2 or Thunderbolt 3 ports, or Windows PC with Thunderbolt 3 ports.(5) 

Simple and S.M.A.R.T

Integrating a Sonnet M.2 4x4 PCIe card into your system is easy—just insert it into a x16 PCIe slot and then start your computer—NVMe compliance ensures the necessary drivers(4) are installed automatically. macOS 10.14.4+, Windows 10, and Linux compatible; the Sonnet M.2 4x4 PCIe uses the operating systems built-in drive formatting utilities to format the SSDs. Drive health monitoring is supported through S.M.A.R.T. (Self-Monitoring, Analysis and Reporting Technology) data reporting, too.


RED Approved Logo

Sonnet was established in Irvine, California in 1986. Since then, we’ve pioneered and brought to market many innovative and award-winning products that enhance the performance and connectivity of Mac, Windows, and other industry-standard computers. Many of our employees (including engineers) have been with the company for more than 20 years (some have been here since the beginning). We have a wealth of knowledge about our current and past products. Should you ever need technical support on one of our products, contact us; we’ll be around to help you.

 Computer hardware shown in photos for illustration purposes; items sold separately.
See Tech Specs Tab for footnotes
Part No.  
FUS-SSD-4X4-E3 Sonnet M.2 4x4 PCIe Card
Warranty 2-year
Form Factor Computer Card
Internal Connectors Four M-keyed (NVMe) M.2 sockets

Mac Logo
SSDs Supported

1-4 Single-sided M.2 2280 NVMe PCIe SSDs(1)
PDF Download

Boot Support


  • Only from a single SSD (not RAIDed)
  • Mac Pro 5,1 or Mac Pro 7,1
  • Any Thunderbolt Mac

Windows, Linux

  • No
RAID Support

macOS(7), Windows, Linux

  • RAID 0, 1, or 5 (Stripe, Mirror, or Parity)
NVMe Support Yes
S.M.A.R.T. Status Data Reporting Support Yes
RoHS Compliant Yes
Package Contents
  • Sonnet M.2 4x4 PCIe Card
  • Documentation

PDF Download


Specifications subject to change without notice.






Computer Compatibility

Mac Pro 5,1(6) (Mid 2010 & Mid 2012) with available full-length x16 PCIe slot

Mac Pro 7,1 (2019) – Use x16 PCIe slot (slot 3, 4, or 5) for full performance

PC desktop or server with available full-length, full-height x16 PCIe slot (PCIe 3.0 slot is preferred)

OS Compatibility

macOS 10.13.6+(8)

macOS Catalina compatible

Windows 10 (64-bit Edition Version 1809 or greater)

Linux Kernel 5.0+

Thunderbolt Compatibility

Mac computer with Thunderbolt 3 or Thunderbolt 2 ports via a Thunderbolt 3 or 2 to PCIe card expansion system with available full-length x16 PCIe slot

Windows computer with Thunderbolt 3 ports via a Thunderbolt 3 to PCIe card expansion system with available full-length x16 PCIe slot

Linux computer with Thunderbolt 2 or Thunderbolt 3 ports via a Thunderbolt 2 or 3 to PCIe card expansion system with available full-length x16 PCIe slot

Technical Notes

  1. You may install fewer than four SSDs now and add more later without needing to reformat existing ones. Only 2280 (80mm—the most common length) length M.2 SSDs and with memory components on only the top side are supported. M.2 SSDs longer or shorter than 80mm don’t fit. M.2 SSDs with with components on both sides don’t fit.
  2. Booting from an external SSD in macOS 10.14.4+ requires enabling external booting in the security preferences that can be set in a command-R (recovery system) boot.
  3. This product’s performance will vary based on the type and number of SSDs used, the CPU speed (for RAID), and the PCIe architecture.
  4. Use of Samsung SSDs in computers running Windows requires the download and installation of NVMe drivers from Samsung; Microsoft Windows inbox NVMe drivers do not support Samsung SSDs.
  5. Performance in a Thunderbolt 3 PCIe expansion chassis limited by maximum Thunderbolt 3 PCIe bandwidth of 2800 MB/s. PCIe bandwidth of Thunderbolt 2 is about half of Thunderbolt 3.
  6. See Apple support note for information for macOS 10.4 (Mojave). See Sonnet FAQ for information for macOS 10.15 (Catalina).
  7. RAID 5 under macOS requires SoftRAID Software, sold separately.
  8. macOS 10.14.6+ supports both 512 and 4k block size SSDs, but macOS 10.13.6 supports only 4k block size SSDs. Today, most SSDs are shipped from the factory programmed with a 4k block size. If your SSDs are programmed with 512 block size, however, and you need to be compatible with macOS 10.13.6, you will need to reprogram your SSDs to a 4k block size. See this tech note for more details.


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Sonnet eGFX Breakaway Reviews

Bare Feats

Sonnet Technologies M.2 4x4 PCIe Card For Mac Pro

The best way to create a fast storage array for your Mac Pro is to install an M.2 PCIe board populated by multiple M.2 PCIe-based flash modules in a striped array. Perfect example: The NEW Sonnet M.2 4x4 PCIe Card. Apple includes it in a list of 'blessed' PCIe boards for the 2019 Mac Pro, but it also works in the 2010 - 2012 Mac Pro.

…because of the 2010 Mac Pro's PCIe bus speed limit, we observed that three striped 970 PRO modules transferred as fast as four. So that opens the door to using the fourth M.2 flash module as a separate volume. For example, you could have a single module as a boot drive running macOS Mojave and the remaining three striped (RAID 0) modules serving as a very fast read/write working project volume and/or scratch volume.

Read Full ReviewLink


Sonnet's M.2 4x4 PCIe Card Brings Absolutely Ridiculous
SSD Speeds to Mac Pro

If you’re looking for the fastest SSD available for the Mac Pro, then this may be the solution for you. When paired with the right SSDs, the Sonnet M.2 4×4 PCIe Card produces speeds of the bonkers variety.

During benchmark tests with the Blackmagic Disk Speed Test utility, I was getting write speeds in that easily surpassed 6,000 MB/s, and read speeds that eclipsed 7000 MB/s.

For comparison’s sake, Apple’s fastest 8 TB SSD produces speeds “only” up to 3400 MB/s, so this setup is capable of running circles around the Mac Pro’s fastest built-in SSD for less money. Watch our hands-on video review for the details.

Read Full ReviewLink



M.2 4x4 PCIe Card SSD Installation Guide

Sonnet M.2 4x4 PCIe Card SSD - A Perfect SSD Storage Solution

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