Differences Between SSD, HDD, and NVMe SSD: Everything You Need To Know

Choosing the right memory drive can be tough, especially given the variety of storage devices available in the market. There are several types of memory solutions which can be quite confusing to understand for an average person. Therefore, it is imperative that you know the key differences between SSD, HDD, and NVMe SSD.

To explain briefly, hard disk drives (HDD) have been the standard storage solution for many years. That is until solid state drives (SSD) came into the picture. SSDs disrupted the storage device market as it could transfer files at double the speed of traditional HDDs. However, with the ground-breaking speeds of NVMe SSDs that can transfer files three times faster than SSDs, it has once again shook up the PC component industry. In short, SSDs are twice as fast as HDDs, and NVMe SSDs are three times as fast as SATA SSDs. 

Below we have outlined a table that will give you an overview of the general differences between SSD, HDD, and NVMe SSD devices.

What is HDD?

Hard disk drives, or HDDs, are traditional forms of storage devices for data and files. It is the slowest option in the data storage categories. HDDs consist of electro magnetic disks that spin to read and write data, which makes the drive slow by default. In comparison, SSDs are much faster as they do not require any disks to store data. However, one area where HDDs are still dominating is the amount of storage they offer. 

What is SSD?

The first Serial Advanced Technology Attachment Solid State Drive, or SATA SSD, was introduced in the year 2000. It comes with a more compact form factor and state-of-the-art technology compared to its predecessor, HDD. The SATA SSD is also commonly known as the origin of SSD technology. It is much faster and operates more silently than HDDs. In other words, unlike HDDs, it doesn’t have any moving parts within it that can cause noise. The introduction of the SSD brought a new era of memory reading techniques which was the very first step to cutting costs when manufacturing storage devices.

What is NVMe SSD?

NVMe, or Non-Volatile Memory Express, is the latest Solid State Drive technology you can find on the market right now. The PCIe interface improved the way data reading and writing is done through multi-channel connectivity. This is done by connecting the storage drive directly on to the motherboard. And unlike HDD and SATA SSD, it is more compact and lightweight, which is quite similar to the form factor of a typical RAM stick.

Differences Between SSD, HDD, And NVMe SSD: What You Need To Consider

It’s really important to understand the differences between SSD, HDD, and NVMe SSD as it can dramatically affect the performance of your system if it is properly optimized. The following table will give you a basic idea of the kind of performance you can expect to get out of HDDs, SSDs, and NVME SSDs. Keep in mind that the numbers are an approximation of general findings. 

Speed

In terms of data transfer speed, HDDs can typically transfer around 130 MB per second and SATA SSDs can transfer up to 500 MB per second. But, NVMe SSDs outperforms all of its predecessors. Since there’s no intermediary between NVMe memory and the motherboard, the direct connection makes it possible to transfer data at an average speed of 3500 MB per second.

Storage

To talk about the storage capacity and capability of these drives, HDDs are still ahead of its competitors. HDDs have a storage capacity that can range between 500GB to 12TB, whereas SATA SSDs have a capacity between 250GB to 4TB. Moreover, NVMe SSDs fall even further behind as it can contain data from 250GB, up to 2TB.

Compatibility

NVMe SSDs are compatible with PCIe connections that allows them to have high transfer rates. The advancement in compatibility really changed how we enjoy gaming, watch content, and do business. These drives are small enough to fit into enclosed spaces and leaves room for your other components in your motherboard. Unlike NVMe SSDs, HDD and SATA SSDs are not as compact or fast. However, they have the best compatibility as they can be used in almost every modern computers. 

In terms of operation, NVMe SSDs undoubtedly prove why you need this storage technology in your system. NVMe SSDs can process 64k commands with 64k queues. Hence, NVMe drives can work with multiple data, commands, and programs simultaneously. It also supports more data formats and functions, unlike its predecessors. Though NVMe SSDs perform better in heavier workloads, it cannot be used in devices that do not support PCIe connection ports. On the other hand, HDD and SATA come with more options in operating systems and BIOS and they are integrated with the AHCI interface out of the box which have widespread hardware support. 

Shape

When you compare the size, NVMe SSD comes with the thinnest form factor and size. You can find 80 millimeter to 22 millimeter SSDs that will give you more room to install other components in your system board. Whereas, SATA SSDs are slightly bigger in size. NVMe devices are soldered with a NAND flash memory chip that makes it more thin. But SATA SSDs don’t always come with NAND or NOR. So, it does not always give you the advantage of having a compact size. But if you look at the general form factor of HDDs, it is the biggest one in this segment. Integrating physical disks and mechanical attachments have always been the reason behind its large shape.

Reliability

When talking about reliability, the HDD comes in last place. If your principle requirement is speed and reliability but not storage capacity, then you can undoubtedly go for NVMe or SATA SSDs. How? Well, HDDs are capable of running for up to 50,000 hours on average. But, if you look at the data from the table, SATA SSDs have an average of 1.5 million working hours. And if you observe the result of NVMe SSDs, there’s no difference between SATA SSDs as it can also perform for 1.5 million hours at an average.

Pricing

The pricing also plays a huge factor here. HDDs are the most affordable. You can have a 1TB HDD at the cost of a 512 SATA SSD. Although you are going to have to compromise on the speed, you will get more disk space to work with. On the middle ground, you will find that the SATA SSD is the most balanced in terms of price, storage, and speed. It provides a standard level of data transfer rate, which is good enough to complete your day to day tasks seamlessly. But, if your primary requirement is speed and not the price, then the latest NVMe technology can give you the best in class performance.

Frequently Asked Questions

Q. What are AHCI and NVMe technology?

A: The AHCI or Advanced Host Control Interface is typically found in HDDs and SATA SSDs. And, the NVMe or Non-Volatile Memory Express is the latest innovation for the Solid State Disk category. The AHCI and NVMe, both technologies work as Valid Interface Technology. Both technologies establish a strong communication between the Host and SSD for seamless data transfer. If you want to know the point differences and speed, AHCI passes up to 16 commands with 1 lane whereas NVMe integrates 64k queues to provide up to 64k commands. So, NVMe plays a very important role in transferring a significant amount of data compared to AHCI.

Q. What are the 2.5 inches and M.2 form factors?

A: The 2.5-inch form factor is usually seen in SSDs and offers SAS (Serial Attached SCSI) and SATA (Serial Advanced Technology Attachment) interface which have the same slot as Hard Disk Drives or HDD. It is typically used for desktop PCs and server based systems to store data. On the other hand, M.2 is the latest innovation of the form factor and is widely regarded as the next generation storage factor for 2.5-inch drives. This form factor requires less physical space and is compatible with the latest PCIe connectors. Key differences here are that it can be attached with the motherboard directly which helps to increase the bus speed for fast data transfer.

Q. What are SATA and PCIe interfaces?

A: There are two types of interface for smooth data reading and writing – Peripheral Component Interconnect Express (PCIe) and Serial Advanced Technology Attachment (SATA). These terms refer to a specific type of slot and technology. SATA has been used for advanced data storage purposes up until the PCIe connector came along. SATA usually comes with a L-Shape connector or port that helps to incorporate the bigger sizes of HDDs and SSDs to your system compared to PCIe. Whereas, PCIe integrates a smaller slot or connector and is capable of transferring two to three times faster data from NVMe devices or a new generation of graphics cards.

Differences Between SSD, HDD, And NVMe SSD: What To Pick?

All of these storage devices have their own purpose and role. HDDs are more affordable and are available with a large amount of space. Whereas, SATA SSDs are the perfect middle ground in terms of price, storage space, speed, and reliability. Lastly, NVMe SSDs take a step forward as it comes with all of the benefits of a SSD, while also having improved speeds and performanc benchmarks.