When it comes to computer storage, Solid State Drives (SSDs) are currently the fastest mainstream option available. With no moving parts and rapid access times, SSDs blew past old school mechanical Hard Disk Drives (HDDs) years ago. But technology keeps advancing, so it’s natural to wonder: is there a drive type even faster than SSDs?
SSD Basics
Before looking at what might surpass SSDs, let’s review what makes SSDs so fast in the first place. Unlike HDDs that use magnetic platters and a mechanical arm, SSDs store data on flash memory chips. This solid state design gives them some major advantages:
- No moving parts – no physical seek time
- Much lower access latency
- Faster sequential read/write speeds
For years, HDDs were the primary storage choice for most consumer PCs. But as SSD costs have lowered, they have taken over as the default system drive for both laptop and desktop computers. Considering a typical SATA SSD can hit 500-550 MB/s sequential read/write speeds and around 10,000-100,000 IOPS for random 4K operations, it’s easy to see why SSDs feel so much faster than HDDs in real-world use.
Challengers to SSD Throne
Even though SSD performance continues to impress, there are contenders aiming to dethrone SSDs as the fastest consumer storage option. Let’s look at some of the top emerging drive technologies that could theoretically surpass SSD speeds.
NVMe SSDs
Currently the most common SSD interface is SATA, short for Serial ATA. SATA has been the standard for connecting storage drives for many years, with SATA 3.0 providing a maximum bandwidth of 600 MB/s.
NVMe, which stands for Non-Volatile Memory Express, is a newer SSD protocol designed from the ground up for much higher speeds. By using the PCIe bus rather than SATA, NVMe SSDs in a PCIe 3.0 x4 slot can hit speeds over 3 GB/s, over 5X faster than SATA SSDs! Even PCIe 3.0 x2 NVMe drives can reach over 2 GB/s read/write speeds.
The significantly increased bandwidth of NVMe allows SSDs to stretch their legs and really show off how fast solid state storage can be. NVMe usage continues to grow, especially in high performance PCs and laptops. But at this point NVMe is an iteration of the core SSD technology, just unrestricted by the legacy SATA interface. Future NVMe revisions will surely be even quicker, but fundamentally still based on NAND flash chips.
3D XPoint
3D XPoint is a new form of non-volatile memory created by Intel and Micron, announced in 2015. It uses a different architecture from NAND flash memory while still retaining the ability to store data permanently without power. Intel Optane products are based on 3D XPoint technology.
By stacking memory cells vertically in three dimensions, 3D XPoint avoids some of NAND’s limitations. It can offer much lower latency and higher endurance than current NAND flash SSDs. Optane drives are already available for consumers, though still quite expensive per GB compared to standard SSDs. Performance is impressive for certain workloads, but not yet surpassing the fastest NVMe SSDs for broader usage.
However, 3D XPoint technology has plenty of headroom to improve. Eventually 3D XPoint or a similar follow-up could claim the overall performance crown. But right now it’s not quite on the level of top tier NVMe SSDs. Still a promising contender though!
DDR5 Memory
DDR5 is the upcoming replacement for the current DDR4 standard RAM in computers. While technically memory and not storage, DDR5 will enable significantly higher memory bandwidth speeds. AMD and Intel platforms are both moving to DDR5 in the near future. Initial DDR5 modules will provide 25% to 50% more bandwidth compared to DDR4.
How does faster system memory relate to storage? NVMe SSD cache! SSDs already frequently use a small amount of ultra fast cache memory, usually DDR3 or DDR4 on drive controllers. With DDR5, NVMe SSDs would have access to much higher memory bandwidth for caching frequently accessed data.
In the future, combined NVMe SSDs + DDR5 memory could potentially offer incredible storage performance. The much faster memory would compensate for the higher latency of solid state storage compared to DRAM. This combination may have a chance of exceeding bleeding edge SSD performance today.
Leading Edge Research
Beyond near term advancements to existing technologies, there are some truly cutting edge research projects looking to completely reinvent digital storage in the coming decades.
RRAM
Resistive RAM (RRAM or ReRAM) is a developing non-volatile memory concept involving changing the electrical resistance of certain materials. RRAM could potentially be structured in three dimensions to maximize density. Early research already shows RRAM access latency and write speeds could surpass current NAND flash by factors of 10-100x!
However, RRAM is still largely in the research stage. There are challenges around endurance and reliability that need to be overcome before RRAM could be a viable SSD replacement. But long term RRAM or related technologies could radically improve storage speeds by optimizing electrical resistance change physics.
MRAM
Magnetoresistive RAM (MRAM) is another novel memory concept, using magnetic charges rather than electrical charges to store data. Like RRAM, MRAM switching physics allow for much faster write speeds and lower latency compared to NAND flash cells. Intel and Everspin already have commercial MRAM products available, but capacities remain small so far.
Current MRAM hardware is more expensive than DRAM while having lower density. However, if manufacturing costs can be reduced, MRAM has huge potential thanks to excellent read/write latency, endurance, and power efficiency. Future dense and fast MRAM or spin transfer torque MRAM (STT-RAM) could be a game changer.
MEMS
Microelectromechanical systems (MEMS) involves tiny mechanical parts etched onto microchips. MEMS mechanical components can function as switches, capacitors, sensors, and more. Ongoing research at institutions like Carnegie Mellon is studying MEMS for possible storage use cases.
MEMS devices could allow massively parallel actuators for storing data at high speeds and large volumes. Multiple MEMS sensors can also operate at low power levels. MEMS storage has the possibility of extremely high throughput unmatched by purely electronic means. But reliably manufacturing billions of microscopic mechanical devices remains highly complex.
Cold Storage
Cryogenic memory using super chilled components is another radical concept being researched. For example, IBM has created prototype storage devices based on cryoelectric RAM. When circuit components are cooled to cryogenic temperatures below -150°C, strange quantum effects take hold that can reduce electrical resistance and enable faster electron transport.
The challenges around cryogenic cooling are obvious, but breakthrough storage materials tuned to cryogenic conditions could massively speed up read/write performance while shrinking physical size. There are likely more undiscovered ultra cold physics effects that could someday revolutionize computing.
Comparison of Drive Speeds
To summarize current and future storage tech, here’s a general comparison of maximum theoretical drive speeds:
| Tech | Max Speed |
| HDD | 200 MB/s |
| SATA SSD | 600 MB/s |
| NVMe SSD | 3,500 MB/s |
| 3D XPoint | 2,500 MB/s |
| DDR5 + SSD | 4,800 MB/s? |
| RRAM | 1,000,000 MB/s?? |
| MRAM | 1,000,000 MB/s?? |
| MEMS | 100,000,000 MB/s??? |
| Cryogenic | ??? MB/s |
Of course, these theoretical limits may be difficult to reach in affordable real-world products any time soon. But the rapid evolution of storage technology means faster SSD alternatives could arrive before we know it. The speed race remains as intense as ever!
Conclusion
SSDs are currently the performance kings when it comes to consumer storage. Yet newer technologies like NVMe and 3D XPoint are already providing SSD competition. Looking farther ahead, cutting edge research into RRAM, MRAM, MEMS, cryogenic memory, and other concepts could bring drive speeds to levels previously unimaginable.
It’s an exciting time in the world of computer storage, with many brilliant minds pushing the limits of next generation data storage. While SSDs have excellent performance today, they may one day seem positively pokey compared to whatever ultimately succeeds them. Storage tech always marches onwards!
