The OWC 4M2 Ultra is a four-slot RAID enclosure that offers high-capacity, super-fast external storage using NVMe SSDs. It features 80Gbps performance and allows you to saturate the Thunderbolt 5/USB4 bus with sequential transfers of up to 7GBps.
The 4M2 Ultra is a black, mostly aluminum box that measures around 4.75-inches tall, 4.5-inches deep, by 2.35-inches wide. Its sides are finned to create more heat-shedding surface area, and it has a Kensington lock port and an AC adapter jack on the back.
One of the standout features of the 4M2 Ultra is its ability to run four SSDs on bus power alone, which is a surprise given the power requirements of Thunderbolt 5. However, it does come with an AC adapter jack for optional power delivery of up to 240 watts.
The 4M2 Ultra's design allows for easy access to its components, with a screw-down backplate that holds two side plates in place. The dual PC board, chips, and fan are sandwiched between the two dual-drive bays, and the front of the enclosure is perforated to allow airflow through to the vents on the back.
The Intel JHL9480 controller allocates each of the 4M2 Ultra's M.2 slots a single PCIe 4.0 lane, providing around 2GBps of bandwidth per slot. This allows for fast performance when running four SSDs in RAID 0, with sequential transfers of up to 7GBps.
To operate the 4M2 Ultra in RAID, you need software, which OWC provides a license for its handy cross-platform SoftRAID. However, the included Pro license expires three years from the date of purchase, although the core functions remain eternally functional.
The 4M2 Ultra is warrantied for two years and has a solid construction that should last well beyond that. It is also significantly faster in every RAID mode than the older 40Gbps 4M2, with write speeds of up to 2GBps and read speeds of up to 6.35GBps.
When tested with various benchmarks, the 4M2 Ultra showed strong performance, with fast read and write speeds in CrystalDiskMark 8 and PCWorld's real-life 48GB transfers. However, it did lag behind in some 4K tests and had disappointing write numbers when transferring large files using the FastCopy utility.
Despite some minor issues with Phison E26 controllers, the 4M2 Ultra is a great way to create speedy large volumes from smaller SSDs. However, users with 80Gbps Macs should avoid using E26-based SSDs, as they may disconnect under load.
Overall, the OWC 4M2 Ultra is a fast and reliable external storage solution that offers high-capacity and super-fast performance. Its ability to combine smaller SSDs into a single large volume makes it a great option for users who need fast and vast external storage.
