In comparison tests, SSDs often prove to be the better storage medium. However, there are many situations in which the old gold hard drive still serves its purpose. We take a closer look at both popular types of storage.

A storage drive allows you to expand the internal storage of your laptop or desktop. Although the average PC today has more storage space than the average user can ever fill, an external drive is still a useful medium for backing up important files. There are two types of storage in circulation today: SSD and HDD.

It is sometimes claimed that the days of the HDD are gradually numbered and that SSD is the superior medium. In reality, however, it is rarely black and white and the comparison between SSD and HDD is also rather gray. Both types of storage have their advantages, but also their disadvantages. We compare different aspects and in different situations when which medium works best.

HDD: a rotating turntable

The differences between SSD and HDD are mainly caused by the architecture of the drive. Therefore, we first need to understand how an SSD or HDD drive is constructed, starting with the HDD, the older of the two. The hard drive is up hard disk and is colloquially simply referred to as a “hard drive”.

The hard drive contains small platters and a magnetic arm. With a little imagination, a hard drive works like a record player. When you copy a file to the hard drive, a very mechanical process is initiated inside, in which a platter slides under the arm that rotates it. The number of revolutions this hard drive can perform per minute determines the write and read speed of your hard drive, expressed in RPM or shots per minute.

Operating an HDD sounds a bit archaic today and that’s why PC manufacturers are increasingly neglecting the technology. You can hardly find an HDD in the internal storage of today’s laptops, but in desktop PCs the cake is more evenly divided between HDD and SSD.

SSD: Storage in a snap

So an SSD solid state drive, does not use mechanical components, but consists of several “blocks” of flash memory chips that are activated by electrical impulses. This doesn’t mean that your SSD requires constant power to function: flash memory, like RAM, is non-volatile and therefore the data is retained even without power.

This way of working has one big advantage over the hard drive: speed. By the time a hard drive has correctly placed the image, an SSD has already read a file. An HDD can easily achieve read speeds of 250 MB/s, in exceptional cases even 500 MB/s, while cheap SSDs often achieve five times that. This means that the latency of an SSD is lower than that of an HDD.

The speed of an SSD depends on various factors. First of all, SSDs come in different shapes and sizes. The first generations of SSDs came in 2.5-inch format, but since the introduction of the M.2 standard there has been more variety. However, the bandwidth used is more important for speed. Like HDDs, SSDs initially relied on SATA, newer models prefer PCIe 3.0/4.0 and NVMe.

Because of these new connection standards, SSD speeds are no longer measured in megabytes, but in gigabytes per second. The SSDs in the more expensive price ranges also have DRAM cache for even faster reading and writing. But an SSD offers more than just speed: This type of storage also operates silently and is more energy efficient for your device (although recent research contradicts this).

Price per gigabyte

So far the balance is in favor of SSD. But the hard drive still has its advantages. For example, the storage capacity of a hard drive is generally higher, although this of course also depends on the type of hard drive, the brand and the price. This also includes the nuance that HDDs require more space than SSDs for the same storage capacity due to the mechanical components.

For example, the hard drive is an interesting option to back up your entire Windows PC. After all, high speed is not that important when it comes to a backup. Even in data centers, hard drives are still the dominant medium for handling the massive amounts of data that come with AI and other technology hype.

Speaking of price, this is perhaps the main reason for preferring a hard drive. The price per gigabyte remains lower for hard drives (average $0.02 to $0.03 per gigabyte) and only appears to be falling. The cloud storage specialist Backblaze assumes that from 2025 HDD storage will be available for one (dollar) cent per gigabyte. We are also seeing prices in the SSD market falling, although less quickly and on average today they are around ten (dollar) cents per gigabyte, again depending on the brand and model.

What lives the longest?

The debate about which type of storage has the longest lifespan is far less unanimous. The body of a hard drive is more delicate than that of an SSD. The arm or the hard drives may become damaged, affecting the performance of the hard drive. This is another reason why mobile device manufacturers prefer SSD. An SSD drive has no moving parts and is therefore more resistant to a fall or other whims of the outside world.

But SSDs also have an expiration date. The Achilles heel lies in the way SSDs are built. Each flash memory cell can only be overwritten a certain number of times before it “dies.” This does not affect the number of read cycles. There are two parameters you can consider when purchasing an SSD to predict its lifespan. You can calculate these numbers yourself, but we leave the complex calculations to qualified mathematicians.

• TBW (terabytes written): the total number of terabytes you can write to an SSD.
• DPDW (drive writes per day): the volume you can transfer per day.

The higher these parameters, the longer your SSD should last, but the amount of data you transfer to your drive every day also affects its lifespan. This can sometimes cause misunderstandings between the user and the manufacturer as the drive fails faster than promised when purchased. Noticeable performance losses only occur when seventy percent of the total capacity is used.

Research from Backblaze seems to show that SSDs last longer on average with equal HDD and SSD usage. During the first four years the failure rate remains similarly high, but from the fifth year onwards the decline rate for hard drives is significantly higher (3.55% compared to 0.92%). There are few numbers on how SSDs perform after five years.

There are a variety of software programs that you can install on your PC to monitor the health of your storage drive, such as CrystalDiskInfo. Manufacturers often also offer supporting software for their products. A third trick is to use Windows PowerShell. Enter the command line Get-PhysicalDisk | Get-StorageReliabilityCounter | Choose Wear in and the value below Carry shows how much of the total capacity you have used.

Beware of denture rot

Then there’s another phenomenon that can put your files at risk and affect both hard drives and SSDs: “bit rot.” This mainly occurs with drives that remain idle for a long period of time. Electromagnetic radiation from the environment can affect the so-called magnetic zones on the hard drive Bit flips Causes. In the case of SSDs, this is due to the weakening of the electrical charge in the cells.

The built-in security mechanisms do not work because the drive is inactive, meaning data on your drive can literally “rot” and be permanently lost. To keep the risk of denture rot as low as possible, it is best to activate your drive once or twice a year. When your drive has reached its end of life, bit rot is almost impossible to prevent and it’s time to move your files elsewhere. Even “classic” storage media such as cassettes, CD-ROMs and USB sticks are not immune to this, although one carrier breaks faster than the other.

SSD or HDD: Conclusion

Which storage type should you choose now? The answer depends on what you need to keep, for what purpose, and what your device(s) support. For files that are still actively used within the organization, the faster copy and read speeds of SSDs are a huge advantage. For more “passive” storage, the hard drive offers a cheaper alternative.

SSD will not immediately completely replace the hard drive and both types of drives can be perfectly combined with each other. Several forecasts suggest that companies will continue to invest in hard drives at least through the end of the decade. The following table summarizes the most important advantages of each carrier type.

SSD will not immediately completely replace the hard drive.

Cloud Storage: Need Another Drive?

Nowadays we do almost everything in the cloud and there is a wide range of services (free or paid) that offer you virtual storage. When you connect to a Microsoft 365 or Google Workspace subscription, you’ll automatically receive a cloud storage package as well. So you may ask yourself whether you still need physical carriers in 2023.

The answer is actually the same as the question of whether you should choose SSD and HDD. Cloud storage has its advantages over physical storage, but it also has limitations. An undeniable advantage of the cloud is its ease of use and availability. Files can be accessed anytime, anywhere as long as you have an internet connection. So no hassle with cables.

Cloud security is a double-edged sword. The services of recognized providers encrypt your files in a vault and also provide the necessary means to secure your account. Often you as a user have to activate this yourself. This is where things often go wrong for companies, which is why cloud vaults are popular targets for cybercriminals. The security of an SSD/HDD is then much easier: What you see is what you get.

Just like an SSD or HDD, cloud storage capacity is not endless. You only receive a small share on the provider’s server. If the amount of storage in the basic formulas is sufficient, cloud storage often offers a cheap solution, but if it is full, you will have to upgrade your subscription and the annual costs can be high.

Again, it’s not an either/or situation, but rather how you can use both types of storage in combination to ensure safe storage of your most important files. We therefore conclude by repeating the golden rule of backups, bolded for emphasis: 3-2-1. Always make sure you three have versions of your files (two copies in addition to the original), op two various carriers, of which A external.