External solid state drives (SSDs) and USB flash drives are two of the most popular types of portable storage devices. Both offer a compact, lightweight way to take your data with you anywhere. But they differ in some key ways that can impact performance, durability, and price.
SSDs use flash memory like flash drives, but are equipped with more advanced controllers. This allows SSDs to offer faster read/write speeds compared to flash drives. However, SSDs come at a higher cost per gigabyte of storage. This often makes flash drives more appealing for everyday basic file transfers and backups, while external SSDs provide a speed boost for tasks like editing videos, photos, or gaming.
This article examines the differences between external SSDs and flash drives in depth. We’ll compare their speed, lifespan, durability, security features, and reliability to help you decide which is a better choice for your needs.
Storage Technology
SSDs and flash drives store data differently. SSDs use NAND flash memory chips to store data persistently, while flash drives use NOR flash memory (Difference Between Flash vs. SSD Storage). The NAND flash memory in SSDs allows for higher densities and faster writes and rewrites compared to NOR flash memory. However, NOR flash offers faster random reads, which is why it’s used in flash drives where small file transfers are common. Ultimately, the different flash memory technologies lead to SSDs having faster read/write speeds, higher storage densities, and better performance for intensive applications like running an OS or programs. Flash drives are slower but sufficient for lightweight storage uses like documents and media files.
Speed
SSDs are generally much faster than flash drives when it comes to read and write speeds. An SSD typically has read speeds of around 550 MB/s and write speeds around 520 MB/s, while a flash drive usually has read and write speeds of just 10-25 MB/s (Source: https://www.minitool.com/backup-tips/flash-storage-vs-ssd.html, https://superuser.com/questions/253579/why-are-usb-flash-drives-so-much-slower-than-ssds). The faster speeds of SSDs are due to the type of memory they use (flash memory) and their higher quality controllers compared to flash drives. This significant speed advantage makes SSDs better suited for tasks that require fast data access or transfer.
Durability
SSDs are generally much more durable than flash drives. This is because SSDs use higher-quality NAND flash memory chips which can withstand a greater number of erase/write cycles before failing. According to MakeUseOf, most flash drives can withstand between 3,000-5,000 write/erase cycles, whereas SSDs are rated for anywhere from 1,000 to over 100,000 write/erase cycles depending on the model [1]. For example, Samsung rates its 860 EVO SSD for up to 150 TBW (terabytes written), equating to approximately 150,000 write/erase cycles [1]. The higher-quality NAND chips make SSDs much more durable for frequent writing and rewriting of data.
Shock Resistance
Solid state drives (SSDs) are generally much more resistant to shock and vibration compared to traditional hard disk drives (HDDs). This is because SSDs have no moving mechanical parts that can be damaged by sudden impacts (Forrest, n.d.). An SSD is essentially a circuit board with flash memory chips soldered onto it. Even though the solder joints could potentially crack under extreme shock, SSDs can withstand much higher G-forces compared to HDDs before becoming damaged.
According to tests by Super User, SSDs can withstand up to 1500G of force, which is a tremendous amount – far more than any everyday bump or drop (How Sturdy (Shock-Proof) is an SSD?, 2014). Quora discusses how SSDs in laptops are very shock resistant due to having no moving parts that can crash into each other (How shock resistant are solid-state drives in laptop computers?, 2018). Overall, SSDs are far less prone to damage from shocks and vibration compared to traditional HDDs.
Encryption
SSDs tend to offer stronger encryption capabilities than flash drives. Most SSDs come with built-in hardware-based encryption like AES 256-bit that encrypts all data stored on the drive, protecting data even if the SSD is lost or stolen. In contrast, flash drives rely on software-based encryption which can be less secure and requires setting up encryption on each device individually (1). Hardware encryption on SSDs also carries minimal performance penalty, while software encryption can slow down flash drives. Ultimately SSDs provide seamless, set-it-and-forget-it encryption that helps keep data more secure.
Sources:
(1) https://www.kingston.com/en/blog/data-security/software-v-hardware-encryption
Lifespan
SSDs generally have a longer lifespan compared to flash drives. According to Stellar Info, flash drives last around 8-10 years with normal usage, while SSDs can last between 8-12 years under normal usage conditions. MakeUseOf states that Samsung guarantees at least 150 TBW (terabytes written) or 5 years for their 250GB 860 EVO SATA SSD, whichever comes first. So while flash drives may technically last close to 10 years, their lifespan is more limited by the number of write cycles whereas SSDs are warranted for both time and writes.
SSDs are built with higher-quality NAND flash memory chips which allow them to endure more write cycles before failure, often around 600-1500 P/E cycles versus just 100-1000 for flash drives. The controllers in SSDs also help evenly distribute writes across all the memory cells through wear leveling algorithms, ensuring no single cell wears out prematurely. Flash drives lack these sophisticated controllers. So over time, heavily used flash drives are more prone to errors and bad blocks/sectors as some cells get overworked. For long-term storage and reliability, SSDs are the better choice.
Sources:
https://www.stellarinfo.com/article/how-long-hard-drives-ssd-flash-drives-last.php
https://www.makeuseof.com/tag/hard-drives-ssds-flash-drives-how-long-will-your-storage-media-last/
Failure Rate
Overall, SSDs tend to have lower failure rates compared to flash drives. According to research by Backblaze, SSDs had an annual failure rate of 1.5% over a four year period, while flash drives saw failure rates of 4-7% per year[1]. The more durable physical construction of SSDs contributes to their improved longevity. While flash drives use simpler circuits enclosed in plastic housing, SSDs contain drive controllers and other advanced components in a solid metal case.
SSDs are also better optimized for sustained performance through wear leveling techniques that distribute writes across all memory cells. In contrast, flash drives tend to have lower quality controllers leading to uneven wear of memory blocks. This reduces the working lifespans of flash drives as heavily used cells will fail sooner[2]. Overall, the superior engineering of SSDs results in markedly lower failure rates.
Price
SSDs generally cost more than flash drives for an equivalent amount of storage. For example, a 128GB flash drive may cost around $20, while a 128GB SSD costs $40-60. There are a few reasons for this price difference:
SSDs use faster, higher quality NAND flash memory chips than basic flash drives. These chips enable the fast speeds but cost more to manufacture. Flash drives use lower grade NAND chips.
SSDs require more advanced controllers to manage the NAND memory and maintain performance. These add to the cost.
The compact, complex construction of SSDs requires more expensive parts like the circuit board and interface connectors. Flash drives have simpler designs.
There are economies of scale advantages for flash drives since they are produced in much higher volumes compared to SSDs. This allows the prices for flash drives to be lower.
In summary, the extra hardware required for SSDs like quality NAND chips, advanced controllers, compact circuit boards, etc. make them cost more than basic flash drives for a given capacity.
Conclusion
The main takeaways of comparing external SSDs and flash drives are as follows:
Solid state drives are faster than flash drives. SSDs offer transfer speeds of around 400-500 MB/s compared to flash drives which max out around 100 MB/s. The higher transfer rate of SSDs allows for quicker file transfers and better performance.
SSDs are more durable. Their lack of moving parts allows SSDs to better withstand shock, vibration and extreme temperatures. Flash drives have more components that can fail.
However, SSDs are more expensive per gigabyte than flash drives. A 1 TB SSD can cost around $100 while a 1 TB flash drive costs around $20. If budget is a primary concern, flash drives provide more storage for less money.
In summary, for superior speed and reliability, external SSDs are the better option even with their higher price. But flash drives can be a suitable lower-cost solution if you just need some additional portable storage and don’t require top performance.
