Using flash drives, also known as USB drives or thumb drives, instead of hard disks for storage is an interesting concept. Both have their advantages and disadvantages, and the best option depends on the specific use case.
Hard disk drives (HDDs) have been the dominant form of computer storage for decades. They rely on spinning magnetic platters to store data. Flash drives are a much newer form of storage that use flash memory chips and have no moving parts. They are smaller, faster, more durable and energy efficient than HDDs. However, HDDs have a lower cost per gigabyte and much higher capacities available.
For most desktop and laptop computers, internal HDDs are still the default storage device. But external HDDs are being increasingly replaced by flash drives for portable storage and file transfer. So what would happen if flash drives became the primary type of storage, even for internal computer storage?
Benefits of Using Flash Drives Instead of Hard Disks
There are several potential benefits to using flash drives rather than hard disks:
- Size – Flash drives are much smaller than hard disks. A 1TB flash drive is about the size of a thumb, while a 1TB hard drive takes up significant internal space in a desktop computer.
- Speed – Flash drives have much faster read/write speeds than HDDs. HDDs are limited by disk spinning speeds of around 7,200 RPM for consumer models. Flash can transfer data almost instantly.
- Durability – Having no moving parts, flash drives are far more durable and shockproof than HDDs with sensitive spinning disks. Flash drives can withstand rugged use in harsh environments.
- Energy efficiency – Flash drives consume a fraction of the energy of HDDs, which have to constantly spin disks.
- Noise – With no moving parts, flash drives operate silently with no noise unlike the audible spinning of HDD platters.
- Heat – Flash drives produce negligible heat compared to HDDs which produce noticeable warmth.
For portable storage and transferring files between computers, flash drives are superior to external HDDs in almost every way. But what about for primary, internal computer storage?
Challenges of Using Flash Drives as Primary Storage
While flash drives have some clear benefits for portable storage, there are also some significant challenges to using them as the primary, internal storage device in computers:
- Cost – Flash storage is substantially more expensive per gigabyte compared to hard drive storage. It would dramatically increase the cost of computers to use 1+ TB of flash rather than HDDs.
- Capacity – The maximum capacities of flash drives are still much lower than HDDs. High-capacity HDDs of 10TB+ are available whereas the largest flash drives are only 2-4TB.
- Rewrite cycles – Flash cells have a limited number of times they can be rewritten before wearing out. HDDs can be rewritten essentially indefinitely.
- File management – The way operating systems handle file writes is optimized for HDDs, not flash. Using flash as primary storage would require rethinking file management.
- Power usage – HDDs only use power when actively reading/writing. Flash chips consume power even when no files are being accessed.
The limited capacities and higher cost of flash storage make HDDs more practical for storing the large amounts of data users often want on their desktop or laptop. Rewrite endurance and power usage are also concerns for primary storage usage scenarios.
Hybrid Drives
Rather than switch completely from HDDs to flash drives, some compromises could combine their advantages in hybrid drives. Some ways hybrid drives can provide the best of both worlds:
- SSHDs (solid-state hybrid drives) – These drives combine a small GBs of NAND flash (ex. 8GB or 16GB) with a traditional HDD, with the flash acting as a cache.
- Dual-drive systems – Computers can be configured with both a large HDD for mass storage and an additional smaller SSD to run the operating system and applications.
- External flash drives – Systems retain a large internal HDD paired with external flash drives for transferring files, backups and other uses benefiting from portability.
These hybrid options allow computers to benefit from flash speed and durability while still having abundant HDD storage capacity. The flash component improves performance for frequently used files like applications and operating system files. But HDDs store the bulk of rarely accessed documents, photos, videos and other media files cost-effectively.
Advances Improving Flash Viability as Primary Storage
There are some advances in flash storage tech that may gradually improve its viability as primary computer storage:
- Increasing capacities – Maximum capacities of flash drives continue to grow rapidly. 16TB and even 32TB drives now exist using newer techniques like QLC flash.
- Falling prices – Flash pricing keeps decreasing, narrowing the gap with HDDs. The $/GB is 2-3x rather than 10x higher for many consumer SSDs now.
- Faster interfaces – New interfaces like PCIe 4.0 x4 further boost flash speed and bandwidth for better performance.
- Improved endurance – Tech like 3D NAND flash increases cell rewrite durability, making flash more viable for write-heavy use cases.
- Improved file systems – File systems optimized specifically for flash like ZFS provide features like read/write optimization and wear leveling.
These kinds of developments may eventually make flash a more realistic option for primary storage, even for desktop PCs and laptops. But currently, the cost and capacity limits still make HDDs preferable for most general-purpose uses.
Use Cases for All-Flash Storage
While HDDs and hybrid options are likely to remain dominant for personal computers for the foreseeable future, all-flash storage makes more sense for certain use cases:
- High-end laptops – Top of the line laptops focused on performance and durability can justify the cost of larger flash storage rather than HDDs.
- Industrial/embedded systems – Rugged, fanless systems meant for harsh environments benefit greatly from the durability and energy efficiency of flash.
- Servers – The performance demands of servers make SSD storage standard for caching and storing critical data that needs fast access.
- High-end desktops – Top-tier gaming and workstation PCs can leverage the speed of flash storage for applications and games even if HDDs are still required for full storage capacity.
These types of use cases show that as the technology continues improving, all-flash storage may become more common even for primary storage. But for typical home and office PCs, hybrid options are likely to be the norm for the foreseeable future.
Conclusion
Switching completely from HDDs to flash drives for primary storage has some clear benefits but also substantial downsides that prevent it from being practical for most general computing uses today. Flash excels at portable storage but isn’t ready to fully replace HDDs in desktop and laptop PCs.
Hybrid options like SSD caches and dual-drive configurations provide the best of both worlds – fast flash performance combined with abundant HDD capacity. As flash storage improves in the future, it may start displacing HDDs in more computing devices, but likely only gradually. HDDs paired with some flash presence will remain the sweet spot for balancing cost, performance and capacity for typical home and office users.