The Complete NVMe Cheat Sheet
You may have heard of NVMe, but are unsure what exactly it stands for or what it does. This cheat sheet breaks down NVMe and gives an overview of how it works in simple terms. It also provides some insights on how you can use it to improve your computer experience, along with an overview of the different kinds of NVMe drives available on the market today.
If you’re new to the world of NVMe, you might be wondering what it is and why it’s such a big deal. Put simply, NVMe is a new type of storage interface that offers several advantages over the older SATA standard. In terms of speed, NVMe can deliver up to 10x the performance of SATA. Additionally, NVMe drives tend to be more reliable and offer better power efficiency.
Advantages of SSDs over HDDs
SSDs offer a number of advantages over HDDs, including:
- faster data access;
- lower power consumption;
- no moving parts, which means less heat generation and potential data corruption;
- small form factor; and
- increased reliability.
How Does NVMe Work?
Non-Volatile Memory Express, or NVMe, is a newer interface for connecting SSDs to computers. SSDs are faster than HDDs because they have no moving parts, which means they can access data much faster. However, the bottleneck has always been the SATA interface, which was designed for HDDs. The NVMe interface was designed specifically for SSDs and uses a PCI Express bus. This means that it can take full advantage of an SSD’s speed potential.
Comparing PCIe-NVMe, M.2, U.2, and SATA Express Drives
PCIe-NVMe drives are the fastest, offering speeds of up to 32 Gbps. M.2 drives are slightly slower, with speeds of up to 22 Gbps. U.2 drives are even slower, with speeds of up to 12 Gbps. SATA Express drives are the slowest, with speeds of up to 6 Gbps. These specifications also differ when it comes to throughput: PCIe-NVMe is the highest at 3,000 MB/s; M.2 is 2,800 MB/s; U.2 is 1,600 MB/s; and SATA Express is 800 MB/s.
Solid State Drive Form Factors
- There are three common form factors for SSDs: 2.5-inch, M.2, and U.2.
- The 2.5-inch form factor is the most common, and it’s used in laptops, desktops, and servers.
- M.2 is a newer form factor that’s smaller and thinner than 2.5-inch SSDs, making it ideal for laptops and small devices.
- The U.2 form factor is mainly found in enterprise storage systems like server arrays.
- Most SSDs come with either SATA or PCIe interfaces, but the latest generation of Intel Optane drives use their own proprietary interfaces as well (more on this below).
What are the differences between M.2, U.2, and PCIe-NVMe drives?
M.2 drives are smaller than U.2 drives and can only be used in laptops or computers that have an M.2 slot. U.2 drives are larger than M.2 drives and can only be used in laptops or computers that have a U.2 slot. PCIe-NVMe drives can be used in any computer with a PCIe slot and are the fastest type of SSD.
M.2 vs U.2 vs PCIe-NVMe – Which Connector Should I Use?
M.2 and U.2 connectors are both available in a variety of lengths and widths, but they are not interchangeable. If you have an M.2 drive, you will need an M.2 connector on your motherboard or expansion card. Likewise, if you have a U.2 drive, you will need a U.2 connector.
PCIe-NVMe Controller Components
NVM Express (NVMe) is a specification for accessing non-volatile storage media attached via the PCI Express (PCIe) bus. The key components of an NVMe controller are the host memory buffer, command processor, and NVM subsystem. The host memory buffer stores commands and data that are being transferred between the host and the NVM subsystem. The command processor fetches commands from the host memory buffer and decodes them.
USB Attached SCSI Protocol (UASP) Support in NVMe 1.3
USB Attached SCSI Protocol (UASP) is a transport protocol that allows for the efficient transfer of data to and from an NVMe storage device. UASP was first introduced in NVMe 1.3 and is now supported by all major operating systems.