Making regular backups of data is crucial for protecting against data loss from hardware failure, accidental deletion, malware, and other threats. An effective backup strategy involves choosing the right backup media for your needs. When it comes to backing up data, two of the main options are hard disk drives (HDDs) and solid state drives (SSDs). This article will examine the key differences between HDDs and SSDs for use as backup devices and provide recommendations on when to choose one over the other.
Having a reliable backup system in place is critical, with one study finding that 93% of companies that lost their data center for 10 or more days filed for bankruptcy within one year (Source: The Importance of Data Backup and Recovery). By understanding the strengths and limitations of HDDs and SSDs for backups, individuals and organizations can implement the right backup solution to protect their vital data.
Cost
When looking at cost for HDDs vs SSDs, it’s important to compare the cost per gigabyte (GB). Generally, HDDs have a much lower cost per GB compared to SSDs. According to Disk Prices, consumer HDDs average around $0.01 per GB, whereas consumer SSDs average around $0.15 per GB. This means an equivalent capacity HDD will be significantly cheaper upfront.
However, when looking at total cost of ownership over time, SSDs may end up being more cost effective. SSDs use less power, put off less heat, and have higher reliability than HDDs. This can lead to lower operating costs and less risk of failure over the lifetime of the drive. Additionally, the price per GB of SSDs continues to fall rapidly. So while HDDs are cheaper today, the long term costs of SSDs are becoming more competitive.
Overall, HDDs offer better value in terms of upfront cost per GB. But SSDs are more competitive when factoring in total lifetime costs. Consider both the short-term price and the long-term value when choosing between HDD and SSD for backup storage.
Capacity
When it comes to maximum capacities, HDDs tend to have much larger options than SSDs. The largest HDDs today can reach capacities up to 5TB for portable drives and up to 16TB for desktop drives (Source 1). In comparison, the largest 2.5″ SATA SSDs top out at around 8TB (Source 2). This makes HDDs better suited for extremely large backups, especially for things like storing huge photo/video libraries or system backups.
HDDs are a more cost-effective solution if you need to backup multiple terabytes of data. The much higher maximum capacities allow fitting more data storage within fewer drives. For massive backups, it can be prohibitively expensive to try using smaller capacity SSDs to reach the same total storage space.
Speed
When it comes to speed, SSDs have a clear advantage over HDDs for both backup and restore operations. SSDs have much faster read/write speeds compared to HDDs. A typical SATA SSD has speeds of around 500-550 MB/s, while a HDD maxes out at around 100-150 MB/s.[https://www.easeus.com/backup-utility/which-is-better-backup-ssd-hdd.html]
This means backing up and restoring data will be 3-5 times faster with an SSD. The faster speed of SSDs is especially advantageous for large backups. Backing up 1TB of data to an HDD over USB 3.0 would take around 5 hours, while an SSD could complete the same task in just over an hour.[https://forum.proxmox.com/threads/backup-restore-low-speed-what-is-wrong.124426/]
Faster backup and restore times are critical when dealing with large amounts of data or systems where downtime needs to be minimized. The speed boost provided by SSDs makes them better suited for server backups, system images, or any application where backup/restore time is a major factor.
Reliability
SSDs tend to have higher reliability and lower failure rates compared to HDDs. According to Backblaze data covering failure rates from 2020-2022, the average annual failure rate for SSDs is around 1.2%, while for HDDs it is around 1.6% (1). This means HDDs have about a 30% higher annual failure rate than SSDs on average. The reliability advantage of SSDs comes from their lack of moving parts – unlike HDDs, SSDs don’t have spinning platters or moving read/write heads that can fail mechanically. However, SSDs do carry risks of failures like flash memory errors and controller issues.
Specifically looking at consumer SSD models, the Seagate ZA250CM10003 had the lowest annual failure rate at 0.73% based on Backblaze’s 2022 report. Most other SSDs had failure rates under 1%, while some HDD models approached 2% annual failure rates (2). On Reddit discussions, users note SSD reliability is still only slightly better than HDDs – though a 0.5% difference in failure rate is a 50% improvement (3). Overall, the lack of moving parts does appear to give SSDs an edge for reliability.
(1) https://www.backblaze.com/blog/backblaze-drive-stats-for-2022/
(2) https://arstechnica.com/gadgets/2023/03/new-data-tracks-failure-rates-of-13-ssd-models-going-back-up-to-4-years/
(3) https://www.reddit.com/r/DataHoarder/comments/11qbpp8/ssd_reliability_is_only_slightly_better_than_hdd/
Longevity
When it comes to lifespan and data retention when a drive is unused or unpowered, SSDs tend to outlast HDDs. According to Superuser, cheap SSDs can retain data without access for about 1 year while good quality SSDs can last 2-3 years. HDDs, on the other hand, often last only a few months without spinning up before data becomes unrecoverable.
This is because HDDs rely on spinning magnetic platters to maintain data integrity. When unpowered for extended periods, the platters can start to demagnetize leading to data loss. SSDs store data in flash memory chips with no moving parts, so they are less prone to degradation over time without power.
Overall, for long-term archival storage of infrequently accessed data, SSDs are the safer bet to ensure data retention for several years, even when unused.
Security
When it comes to encrypting your backup drive, both HDDs and SSDs offer secure options. SSDs have built-in hardware-based encryption that encrypts all data stored on the drive (Kingston). This type of encryption happens at the hardware level between the OS and system BIOS using AES 128-bit or 256-bit algorithms. SSD hardware encryption is efficient and doesn’t impact performance (Crucial).
HDDs can utilize software-based encryption like BitLocker on Windows (Microsoft). The downside is this can impact performance since the encryption/decryption happens at the software level. However, HDD encryption options like BitLocker integrate with Windows and manage encryption keys.
The built-in hardware encryption of SSDs is convenient and efficient. But HDDs offer more flexibility with software encryption options. Ultimately, both HDD and SSD backups can be secured through encryption.
Portability
When it comes to ease of transport, SSDs have a clear advantage over HDDs. SSDs are much smaller and lighter since they have no moving parts. According to Space.com 1, a typical 2TB external HDD can weigh over 400 grams, while a comparable external SSD weighs around 45 grams. This difference in weight is substantial when carrying a backup drive around.
The small size of SSDs also makes them easier to slip into a bag or pocket. As an example, the popular SanDisk 1TB Extreme Portable SSD measures just 49 x 139 x 170 mm and weighs 79 grams 2. An equivalent portable HDD would be almost 3 times thicker and over 5 times heavier. For users who need to transport their backup drive frequently, the superior portability of SSDs makes them a better choice over bulkier and heavier HDDs.
Use Cases
When deciding between a HDD or SSD for your backup, consider what you will primarily use the drive for. Each has advantages for different use cases:
Best for HDD backups:
- Backing up large volumes of data like photos, videos, music libraries
- External desktop backup drives that stay in one place
- Archival or offline backups accessed infrequently
- Backups on a tight budget due to lower cost per GB
Best for SSD backups:
- Backing up critical system files and programs
- External portable backup drives for traveling
- Backups needing frequent quick access to data
- Backups of sensitive/encrypted data requiring security
The use cases you plan to rely on the backup drive for will determine if HDD or SSD is a better fit.
Recommendations
Overall recommendations for HDD vs SSD backups for different needs:
For most home users looking to back up personal files like documents, photos, videos, and music, a HDD is likely the best option. HDDs offer much larger capacities for lower prices compared to SSDs. Unless you need to frequently access backed up files or have a small amount of data, the faster speeds of an SSD are not necessary for a home backup device.
For power users, creative professionals, and businesses that deal with large files like high-resolution photos and videos, an SSD backup drive provides much faster transfer speeds and access times. The increased durability and reliability of SSDs also makes them a better choice for frequently accessed backup drives.
Gamers and IT professionals may benefit from the speed of an SSD for backing up game libraries or system images. But a high capacity HDD would be required for archiving large game libraries or system backups over time.
For a primary real-time backup of an operating system or critical applications, an SSD is recommended over an HDD for faster speeds and reliability. Use an HDD for any secondary backups or archives.
When backing up sensitive personal or business data, SSDs offer more security as data can be instantly erased. HDDs require time-consuming overwrite procedures to fully erase data.
For a portable external backup drive that will be transported, an SSD withstands vibration and shocks better than an HDD.
In summary, SSDs are better for speed, frequent access, reliability, durability, and security. But HDDs offer far more affordable capacity for archiving and cold storage of backups.
