OWC Best Practice: Choosing the Best NVMe SSD for the OWC Express 1M2

Created on: February 15, 2024
Last updated: February 15, 2024

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The OWC Express 1M2 can reach speeds over 3100 MB/s. However, the host computer and the quality of the NVMe SSD selected will cause variance with performance. The OWC testing lab reviewed dozens of NVMe SSDs over multiple host computers to better understand how performance was impacted. There are several factors that OWC recommends considering before choosing a NVMe SSD and connecting the OWC Express 1M2 to a host computer. Understanding that both the host computer and quality of the NVMe SSD can impact performance is very important to understand.


Host Computer Specifications

The performance of the OWC Express 1M2 will be determined by the connected host computer port. The OWC Express 1M2 can connect to several different ports including USB4, USB3, Thunderbolt 4, and Thunderbolt 3. USB4 (up to 40GB/s) users should experience faster speeds than a user connecting to Thunderbolt 3 (up to 10GB/s). OWC recommends reviewing the manufacture specs for the host computer to understand what ports are available and the expected performance of those ports.

Flash Memory and DRAM

High-quality NAND flash memory such as SLC (Single-Level Cell), TLC (Triple-Level Cell) and MLC (Multi-Level Cell) should be considered when choosing a NVMe SSD. SLC is often the most durable and expensive flash memory. NVMe SSDs can also be equipped with a DRAM cache. The cache processes drive function information independently from the flash memory. Keeping these processes separate allows for better data rates when reading and writing to the NVMe SDD. Manufactures should list this information as some form of NAND flash components.


A high-quality controller is very important to consider for efficient drive performance. Reputable manufactures will design controllers that are consistently fast and reliable. OWC recommends seeking reviews of current controllers on the market from reliable sources to understand performance expectations. Manufactures should list this information as some form of controller or chipset.

PCIe Generation

The PCIe generation of a NVMe SSD can determine drive performance. PCIe 3.0 and PCIe 4.0 are the most commonly available options on the market. PCIe 4.0 is stronger and provides more bandwidth for moving data. PCIe 4.0 also requires less power to operate which keeps drives cool. NVMe SSDs that have a PCIe 4.0 interface are ideal for data-intensive workloads.


Considering a NVMe SSD's endurance and reliability ratings will help identify high quality drives. Manufacturers should list some form of Total Bytyes Written (TBW) and Mean Time Between Failures (MTBF). Higher TBW and MTBF indicates a durable and reliable NVMe.

Warranty and Support

The warranty offered by the manufacture should be considered when identifying a high-quality drive. Longer warranty periods typically indicate the company's confidence in the drive’s durability and reliability. Access to knowledgeable and responsive customer support can be vital if any issues are encountered.

Budget Considerations

Set a budget for the desired NVMe SSD. A variety of options are offered on the market. Take the time to compare the features covered in this article along with drive costs to make an informed decision. Considering these features will allow for the confident purchase of an affordable and reliable NVMe SSD.

OWC Best Practice Choice

OWC recommends the OWC Aura Ultra IV as a great all-around choice when you consider the features covered in this article.