Storage technology has evolved by leaps and bounds since the dawn of the computer age. Today's leap forward is NVMe, a storage system that promises to exponentially increase the bandwidth available to storage devices. Here's what you need to know about NVMe SSDs.
NVMe was created because newer SSDs saturate even SATA III bandwidth. Has a theoretical maximum of 6 Gb/s (that's gigachunks , eight times smaller than a gigabyte), the SATA III connection is quickly saturated by a high-quality SSD in good conditions. But flash storage can achieve speeds well beyond what SATA III allows. To free silicon from its SATA shackles, NVMe was created.
Rather than doubling the bandwidth of SATA III by using two interfaces for each drive, a cumbersome, expensive and power-hungry idea, the industry has instead started to focus on NVMe drives as the future of digital storage. For the fastest and most scalable storage devices, NVMe is the pinnacle of our time.
When sending data over the PCI Express bus, NVMe can use up to four PCI Express lanes, sending data in parallel. Each PCI Express lane can handle approximately 4 GB/s or 32 GB/s. That's more than five times faster than the theoretical maximum of SATA III. While no device ever achieves these speeds, the headroom available for SSDs to exploit is enormous. As a result, transfers occur as fast as the operating system and storage bus can handle them, exponentially increasing data transfer speed and increasing machine productivity.
NVMe SSDs are the fastest SSDs you can buy today. They combine already fast flash memory with the fastest available connection standard available on most PCs. If you care about speed, NVMe is where you'll find it.
Most modern consumer NVMe drives are sold in M.2 format. This eraser-sized storage format contains enough space for an impressive amount of NAND cells and is usually connected via a specially reserved M.2 slot on the motherboard. An M.2 card can also be mounted on a PCI Express card that accepts M.2 SSDs, which is actually how some of the commercially available NVMe SSDs in PCI Express form factor are made. Other manufacturers solder the chip in place, but the performance difference is only noticeable at the highest levels of use and reliability.
There is no speed advantage to a PCI Express form factor for NVMe SSDs, as the electrical connection between the storage controller and the processor is the same in both cases. A PCI Express card may provide better cooling, depending on fan and heatsink configurations, but this is a natural consequence of the PCI Express card's larger size, which can accommodate more ancillary components on the printed circuit board.
Image credit:Dmitry Nosachev
