What is an SSD?

A solid-state drive (SSD) is a storage device that allows reading, writing, and storing data permanently without a constant power source. 

They can be used as internal or external drives. And because they don't have moving parts when retrieving data they are getting smaller. For example, one of the most common forms is the 2.5-inch SSD, which is about the size of a deck of cards.  

Unlike hard disc drives (HDDs), an SSD storage device offers practically instant access times as the data is stored in microchips. The main difference between an SSD and an HDD is how data is stored and accessed. HDDs store data on a series of spinning magnetic disks called platters. SSDs read and write data to underlying interconnected flash memory chips made of silicon. Manufacturers build SSDs by stacking chips in a grid to achieve different densities.  

There are several forms of SSD. M.2 SSDs, for example, are small – about the size of a 5-piece pack of gum. U.2 drives, meanwhile, use a similar but unique motherboard connection to M.2 but are available in 2.5-inch form. Because of the larger form factor, U.2 has a higher storage capacity – around 4TB+ compared to the 2TB maximum from most M.2. 

An SAS SSD, on the other hand, is a NAND flash-based storage or caching device designed to fit in the same slot as an HDD and use the SAS interface to connect to the host computer. The most common drive form factors for a SAS SSD are 2.5-inch and 3.5-inch. SAS SSD bandwidth options include 3 Gbps, 6 Gbps and 12 Gbps. 

The History of SSDs  

Perhaps surprisingly, SSDs are nothing new. They first hit the technology scene back in the 1950s when they were used in first generation computers that used vacuum tubes for logic circuitry. They operated via two similar technologies: card capacity read-only storage and magnetic core memory. 

However, SSDs fell out of favor in the late 1950s and 1960s with the growth in popularity of cheaper storage systems such as drum memory, which were magnetic data storage devices. 
SSDs didn’t go away though, and by the1970s they were back – although they were extremely expensive. Because of this, they were not widely used until Dataram launched its Bulk Core SSD in 1976. But the cost was still eye-watering. A Bulk Core set-up, including a controller board and 256KB of storage, cost around $8,000 in 1977, which is equivalent to about $39,000 today. At that pricing rate, according to PC World, a 1TB SSD would have cost north of $121 billion! 

From the late 1970s, SSDs developed further and by the 1990s, flash-based SSDs were introduced and started gaining popularity globally, but they were still very costly compared to today’s prices. 

All that changed in 2003 when Transcend introduced cheap flash SSDs with a Parallel Advanced Technology Attachment (Parallel ATA or PATA) connector that cost as little as $45. 
By the end of 2012, reliable enterprise flash drives for high-performance applications were the norm. The increasing need for speed, high performance, and reliability were and still are the critical factors behind the growth and advancement of SSDs over HDDs. 

An SSD is just a thin wedge of NAND flash memory - exactly same as the one in your USB drive, but instead of being encased in a thin stick, an SSD is put inside a shell along with an interface connector for transferring data between a computer's central circuit board and storage devices providing enhanced performance. 

SSD Interfaces 

SATA (serial advanced technology attachment) is a popular interface for SSD technology. SATA communication transfers data one bit at a time, rather than in several parallel streams. Despite the apparent advantage of the parallel model, in practice serial transmission is less susceptible to interference, allowing SATA to operate at significantly higher speeds than PATA, which it has pretty much replaced. The serial model also allows for simpler and slimmer cabling. 

Non-Volatile Memory Express (NVMe), on the other hand, is a storage interface and transfer protocol with the highest throughput and the fastest response times using the Peripheral Component Interconnect Express (PCIe) bus. NVMe SSDs are becoming the go-to choice for data centres worldwide, primarily due to their speed and reliability. 

For more information about NVMe, head to the Techbuyer blog page.  

Techbuyer offers a wide range of SSD options and HDDs to suit any business and every budget. Our technical experts will be able to guide you as to the best choice for you and your business. In addition to saving you money, all our SSDs and HDDs come with a cast-iron three-year warranty for added peace of mind.