The ultimate performance drive for Mac Pro and PC towers. Achieve speeds over 6,000MB/s, and store high-resolution footage, photos, and games.

PCIe 3.0 M.2 NVMe SSD Storage Solution
- Supercharges Mac and PC: ideal for Mac Pro 2019, Mac Pro 2012 or 2010, and PC towers
- Work faster: over 6,000MB/s real-world speed in RAID 01
- Store more: space for up to 32TB of critical footage, images, files and games
- Bootable: start working in seconds2
- Slot-powered: no extra power cables needed
- Includes SoftRAID: robust software for creating, monitoring, and managing advanced RAID sets
- Deployment ready: pre-configured solutions undergo performance verification
- Highly versatile: installs into a full-height, half-length x8 or x16 PCIe 3.0 or 2.0 slot3
- Plug and play: no drivers needed

Our Not-So-Secret Winning Formula
When OWC launched its first Solid State Drive (SSD) in 2010, it was engineered to deliver the same attribute formula that Mac and PC users expected from OWC external storage solutions:

High performance + high reliability + affordable price = OWC Difference
Nearly a decade later, our commitment to that winning formula remains steadfast as we push the boundaries of leading-edge SSD development with the Accelsior 4M2. It’s ideal for uncompromised data intensive, high-bandwidth needs like large format video editing, virtual reality/augmented reality/mixed reality environments, high transactional and complex calculation applications, and extreme gaming.

Under Accelsior 4M2’s s finned heat sink cover that provides silent throttle-free cooling reside four Phison E12 M.2 NVMe SSDs with up to 32TB of storage capacity. These “blade” style SSDs utilize Triple-Level Cell (TLC) 3D NAND with SLC caching and 7% over-provisioning.

All those “ingredients” combine to deliver over 6,000MB/s real-world read and write speeds with the highest reliability possible to satisfy the biggest storage performance appetite.

The Performance Advantage of NVMe
Non-Volatile Memory Express (NVMe) is a communication standard specifically built to optimize the performance of modern flash technology. It enables significantly faster SSD performance vs an SSD using the SATA interface, a communication protocol that was originally designed for hard disk drives. With NVMe SSDs powering its heartbeat, Accelsior 4M2 delivers extreme data rates that will change the way you work or play.

Highly Versatile with Mobile Possibilities
Whether you have the Mac Pro 2019, a Mac Pro 2012 or 2010, or PC tower, Accelsior 4M2 can go to work for you. As a half-length x8/x16 compatible card, this game-changer offers the versatility you need so you’re not tied to one slot size or limited by a space-confined computer case.

You can also enjoy the performance boosting benefits of Accelsior 4M2 with your Thunderbolt 3-equipped notebook computer, iMac workstation, or slot filled gaming rig. It’s plug and play easy with a PCIe expansion chassis like the OWC Mercury Helios 3s (sold separately).4 Helios 3S lets the Accelsior 4M2 flow with your workflow by offering up to 2,500MB/s real-world read/write performance in the field on your notebook.5 Once back at your desk, the choice is yours…keep Accelsior 4M2 in the Helios 3S or install it into your Mac Pro 2019 to enjoy its blistering fast 6,000MB/s capabilities.

More Lanes = Faster Throughput
Accelsior 4M2 was designed with a PCIe switch to let your computer address each of the M.2 NVMe drives at full x4 PCIe speeds instead of hard-limiting each drive to x2 PCIe speeds. When running in JBOD, where all four drives are typically not accessed at the same time, each drive has the unlocked capability to run at full speed.

2 to the Second Power
When over 6,000MB/s real world speed and 32TB of capacity isn’t enough to satisfy your needs, you can RAID two Accelsior 4M2 cards together to experience out of this world performance.

Change Your Reality
Accelsior 4M2 offers performance gains in so many diverse ways that it will change the reality of how you use a storage solution:
- Stream and edit high-res video and graphics files without a glitch.
- Experience faster previews, renders, and processing in VFX programs.
- Keep page scenery and textures looking sharp and flowing uninterrupted in virtual reality environments.
- Ensure augmented reality visualizations look lifelike.
- Change game levels seamlessly and play flight/driving/MMO games with continuously changing scenery and heavily modded games without micro-stuttering.
- Give your computer a significant speed boost with improved system “snappiness”, a fast OS boot drive, or a bottleneck-free scratch drive.

The Most Powerful RAID Tool on the Planet.
SoftRAID is the world’s fastest and most flexible application to configure, maintain, and protect your RAID volumes on Mac and PC. OWC enclosures include 3 Years of SoftRAID Premium.
- High-Performance RAID 0/1/4/5/1+0 (10) volumes
- Predictive Health Monitoring proactively notifies of Volume and Disk issues well before failure — provided on your computer and remotely
- Seamless Cross-Platform Sharing with support for Apple-formatted APFS and HFS+ SoftRAID volumes between Mac and Windows at no additional cost
- 35+ Years of Experience of Pro Support to provide peace-of-mind with setup help, ongoing questions, or urgent disk issues
- And many more unique features.
M1 Macs require macOS 11.3 or later. SoftRAID is licensed per computer.

Professional Grade = Ready to Work
We understand having confidence in gear reliability is paramount to creative professionals. That’s why every Accelsior 4M2 pre-configured solution undergoes a multi-step performance certification prior to shipping. This ensures your Accelsior 4M2 arrives operating properly and immediately ready for demanding use.

Includes
(1) OWC Accelsior 4M2 PCIe Adapter Card
(1) Support Manual for OWC Accelsior 4M2 (digital)
3 Year OWC Limited Warranty

Detailed Specs
Drive Bays:
4 bays supporting: M.2 drives
Supports NVMe M.2 SSDs with 2280 form factor and "M Key" connector type. Single- and double-sided SSDs are supported.
NVMe SSDs with a heatsink will not fit and are not supported.
RAID Support: Yes
Form Factor: M.2 - 2280 "M Key"
Drive Interface: PCIe 3.0 x8, NVMe 1.3
RAID Capable: Yes
RAID Features: Software RAID Capable
Internal Connectivity: (4) NVMe M.2 Slots (PCIe 3.0 x4)
Card Interface: PCIe
PCIe Bus Interface: PCI Express 3.0 x8
PCIe Form Factor: PCIe x8 full height, half length , Compatible with PCIe x8 slots or larger
PCIe Bandwidth Allocation: Advanced Switch: A total of eight lanes of bandwidth are available with any single drive using up to four lanes max.
Chipset / Controller: ASMedia ASM2824
Mac OS Compatibility:
macOS 10.13 High Sierra
macOS 10.14 Mojave
macOS 10.15 Catalina
macOS 11.x Big Sur
macOS 12.x Monterey
macOS 13.x Ventura
macOS 14.x Sonoma
macOS 15.x Sequoia
PC OS Compatibility:
Windows 10 64-bit Edition
Windows Server 2016
Windows Server 2022
Windows 11
Other OS Compatibility: Linux kernel versions 5.4 or later
Power/Activity LED: Yes
Dimensions: Height: 12.6 cm (5.0 in) , Length: 18.1 cm (7.1 in) , Width: 2.2 cm (0.9 in)
Weight: 381.0 g (0.84 lbs)
Certifications: CE , FCC
RoHS Compliant: Yes
Ambient Temperature: Operating: 41°F to 95°F (5°C to 35°C) , Non-Operating: -4°F to 140°F (-20°C to 60°C)
Altitude: Operating: -304.8 m to 3,048.0 m (-1,000 ft to 10,000 ft) , Non-Operating: -304.8 m to 12,192.0 m (-1,000 ft to 40,000 ft)
Humidity: Operating: 8% to 90% non-condensing , Non-Operating: 5% to 95% non-condensing

1. NVMe SSDs with a heatsink will not fit and are not supported.
2. Backward compatible with PCIe 2.0 slots with reduced speeds.
3. Performance in a Thunderbolt 3 PCIe expansion chassis limited by maximum Thunderbolt 3 PCIe bandwidth of 2800MB/s.
4. Bootable using a single, independent M.2 startup disk, with the other three M.2 SSDs configured as independent volumes or as a software RAID (SoftRAID or Apple RAID). Mac Pro (2010-2012) requires macOS 10.14.6. Mac Pro (2019) requires macOS 10.15.1 or later.
5. When installed, the following SSDs will only be compatible with Windows 10 systems: Hynix Gold P31, Samsung PM981a.
6. The LED function of this product will be disabled and not function if used with an 8TB OWC Aura Ultra IV MVMe M.2 SSD (OWCP4U8T1PT08).