NVMe, which stands for Non-Volatile Memory Express, and SSD, which stands for solid state drive, are two different interfaces used for storage drives in computers. Both offer much faster speeds than traditional hard disk drives (HDDs), but NVMe is newer technology and offers some advantages over SATA SSDs.
What is NVMe?
NVMe is a host controller interface and storage protocol created specially for non-volatile memory drives like SSDs. It was designed from the ground up to take advantage of the low latency and internal parallelism of SSDs.
Some key attributes of NVMe:
- NVMe operates over the PCIe bus, rather than SATA or SAS bus
- Enables much higher speeds than SATA – up to 4 GB/s per lane
- Designed to better utilize the parallelism of SSDs with up to 64K queues and 65,536 commands per queue
- Lower latency and higher input/output operations per second (IOPS) than SATA SSDs
- Designed from the ground up for non-volatile memory like NAND flash
In summary, NVMe is an optimized, high performance host controller interface designed specifically for SSDs and other non-volatile memory. It allows SSDs to operate at full speed by removing legacy protocol overhead and limitations.
What are SATA SSDs?
SATA SSDs are solid state drives that connect via the Serial ATA interface. This is the same interface used for connecting hard drives and optical drives.
Some attributes of SATA SSDs:
- Use the SATA 3.0 interface which tops out at 600MB/s
- Compatible with the SATA ports on consumer PCs and laptops
- Typically connect via the 2.5 inch form factor
- Often use the AHCI command protocol designed for hard drives
- Peak sequential read/write speeds around 500-550MB/s for SATA 3.0 drives
While SATA SSDs are much faster than HDDs, they are held back by the legacy SATA interface which was designed around the needs of mechanical hard drives. This limits their maximum theoretical speeds to around 600MB/s.
NVMe vs SATA SSD Speed Differences
So how much faster is NVMe compared to SATA SSDs? Let’s look at some speed comparisons between SATA 3.0 SSDs and PCIe 3.0 x4 NVMe SSDs:
Sequential Read Speed
- SATA 3.0 SSDs: up to 550MB/s
- PCIe 3.0 x4 NVMe SSDs: up to 3,500MB/s
Sequential Write Speed
- SATA 3.0 SSDs: up to 520MB/s
- PCIe 3.0 x4 NVMe SSDs: up to 3,000MB/s
Random Read Speed (4KB QD32)
- SATA 3.0 SSDs: Up to 90,000 IOPS
- PCIe 3.0 x4 NVMe SSDs: Up to 750,000 IOPS
Random Write Speed (4KB QD32)
- SATA 3.0 SSDs: Up to 80,000 IOPS
- PCIe 3.0 x4 NVMe SSDs: Up to 580,000 IOPS
As you can see from these benchmarks, NVMe SSDs using a PCIe 3.0 x4 interface offer around 6-7x higher sequential read/write speeds compared to SATA 3.0 SSDs. The difference is even more substantial for random access performance, with NVMe providing up to 8-10x higher IOPS.
This massive difference is due to NVMe’s ability to utilize much more PCIe bandwidth (up to 4GB/s per lane) and its reduced latency and overhead from eliminating the SATA protocol.
Real-World Performance Differences
Synthetic benchmarks give us an idea of the maximum theoretical performance difference between NVMe and SATA SSDs. But how does this translate to real-world use?
For many common workloads and applications, SATA SSDs are actually not that far behind NVMe SSDs in perceived experience. Both will feel extremely fast compared to hard drives.
However, for more demanding workloads there can be a noticeable difference. Here are some examples where NVMe SSDs can provide meaningful speedups over SATA SSDs:
- Transferring large files: NVMe can reach peak transfer speeds of over 3GB/s compared to 500MB/s for SATA SSDs.
- Video editing: Faster speeds allow real-time editing of high bitrate 4K/8K video footage.
- Data analytics: Faster access to huge databases for running complex queries.
- Virtualization: Support more virtual machines with reduced I/O latency.
For average users who just browse the web, use office applications, or play casual games – a SATA SSD will still provide a very responsive experience. NVMe becomes more beneficial for power users running heavy workloads that can take advantage of the increased performance.
PCIe 3.0 vs PCIe 4.0 NVMe SSDs
NVMe SSDs were originally designed to run on the PCI Express 3.0 interface which provides up to 4GB/s of bandwidth per lane. However, the PCIe 4.0 standard doubles this to 8GB/s per lane.
This allows newer PCIe 4.0 NVMe SSDs to reach even higher theoretical speeds:
- PCIe 3.0 x4 NVMe SSDs: Up to 4GB/s per lane, so around 4GB/s total.
- PCIe 4.0 x4 NVMe SSDs: Up to 8GB/s per lane, so around 8GB/s total.
Here are some maximum performance comparisons between PCIe 3.0 and PCIe 4.0 NVMe SSDs:
Sequential Read Speed
- PCIe 3.0 x4 NVMe SSDs: Up to 3,500 MB/s
- PCIe 4.0 x4 NVMe SSDs: Up to 7,000 MB/s
Sequential Write Speed
- PCIe 3.0 x4 NVMe SSDs: Up to 3,000 MB/s
- PCIe 4.0 x4 NVMe SSDs: Up to 5,000 MB/s
Random Read Speed (4KB QD32)
- PCIe 3.0 x4 NVMe SSDs: Up to 750,000 IOPS
- PCIe 4.0 x4 NVMe SSDs: Up to 1,000,000 IOPS
Random Write Speed (4KB QD32)
- PCIe 3.0 x4 NVMe SSDs: Up to 580,000 IOPS
- PCIe 4.0 x4 NVMe SSDs: Up to 700,000 IOPS
While PCIe 4.0 offers higher bandwidth and speed ceilings, real-world usage is still catching up. For most consumers, a PCIe 3.0 NVMe SSD will provide great performance. However PCIe 4.0 SSDs allow headroom for more demanding workloads.
To benefit from PCIe 4.0 NVMe SSD speeds requires a compatible motherboard and processor. AMD Ryzen 3000 and newer CPUs and X570/B550/A520 chipset motherboards added support for PCIe 4.0, while Intel platforms currently remain at PCIe 3.0 speeds.
NVMe vs SATA SSD Price
Historically, NVMe SSDs carried a price premium over similar capacity SATA SSDs due to being newer technology. However, in recent years prices have converged and you can often find NVMe SSDs selling for similar prices as SATA:
| Capacity | SATA 3 SSD Price | NVMe SSD Price |
| 250GB | $40 | $45 |
| 500GB | $60 | $65 |
| 1TB | $90 | $100 |
| 2TB | $170 | $180 |
While low capacity NVMe drives still sometimes carry a small premium, at higher capacities the pricing is very close. And performance focused NVMe SSDs are now available across a wide range of budgets.
This makes NVMe SSDs very compelling for new PC builds – they offer substantially better performance with little or no price penalty compared to SATA SSDs.
Conclusion
To summarize the key differences between NVMe and SATA SSDs:
- NVMe SSDs offer much higher sequential read/write and random access speeds due to NVMe’s ability to utilize more PCIe bandwidth.
- Peak theoretical performance of NVMe SSDs is about 6-10x higher than SATA SSDs.
- For average users, SATA SSDs are still very fast. NVMe provides more benefit for demanding professional workloads.
- Newer PCIe 4.0 NVMe SSDs roughly double the performance of PCIe 3.0, but require PCIe 4.0 compatible hardware.
- NVMe SSD prices have come down dramatically and are now close to SATA SSDs of the same capacity.
In summary, while both SATA and NVMe SSDs are much faster than hard drives, NVMe SSDs provide substantially better peak performance. NVMe SSDs have largely closed the price gap with SATA SSDs, making them a clear choice for new PC builds focused on optimal performance. For workflow’s that can take advantage of the speed, NVMe SSDs provide a worthwhile boost over SATA.
