Comparison between NVMe and SSD

Comparison between NVMe and SSD


The world of computer storage has gained a lot of attention in the last decade. First we saw the traditional HDDs (Hard Disk Drives) getting replaced by much faster and now even affordable SSDs (Solid State Drive). And now we have much faster flash memory technology in the form of NVMe (Non-Volatile Memory Express).

What is NVMe?

While a lot of people already know about SSDs, the same cannot be said by NVMe. This is actually a flash memory technology which can be manufactured in several different form factors/interfaces, like M.2. It is developed exclusively for the SSDs by vendors like Samsung, Intel, Dell, Seagate, and Sandisk.

Just like SATA and SCSI, NVMe is also designed for taking advantage of properties of the random-access, memory-based, pipeline-rich storage. With NVMe, only one message is required for 4KB transferred while two were required in the past. Moreover, it can also process more than 65,000 queues as opposed to one. This can be highly beneficial for servers that process several simultaneous I/O requests. However, such high speeds are not really required for consumer PCs.

NVMe: Created for SSD

If you have been following the news about SSDs in the last couple of years, you might already know that SSDs are struggling with problems, like legacy storage buses. While SAS and SATA offer a lot of bandwidth for the hard drives, they cannot do the same for faster SSDs.

But fortunately, a bus technology with high-bandwidth was in place already in the form of PCIe. This is the data transport layer which lies underneath the graphics and other add-on cards. While expansion solutions for PCIe are available, they too rely on SATA and SCSI protocols. Needless to say, a newer, better approach was needed.

Drivers put in place but connectors and BIOS are not

One of the most important benefits of NVMe is the fact that you are not really required to think about the drivers showing up. But the BIOS support is pretty much lacking. Without a BIOS which is NVMe aware, you cannot boot from the NVMe drive. However, anyone that has a M.2 or x4 PCIe connector can take advantage by using NVMe as a secondary storage.

Same is the case with connection. In many of the earlier NVMe expansion cards you will see Gen 3 PCIe slots. This is because all the 2.5-inch NVMe SSDs use SFF-8639 connector which is exclusively designed for NVMe but is only available with high-end servers.

So, while NVMe is definitely a vast improvement from SSDs, the new technology is still somewhat not entirely developed. Or buyers can find it difficult to use them as a lot of software and hardware don’t support it yet. Also, as compared to SSDs, you don’t get a lot of options with NVMe. Last but not the least, consumer PCs doesn’t really need a storage that is so technically advanced. So, even when the compatibility problem is resolved, it will still be only applicable to professional environments.