SATA vs. PCIe: What’s the difference?

BLOG 2022.08.31

SATA vs. PCIe: What’s the difference?


With far superior data transition speed, SSD (Solid State Drive) has gradually superseded HHD (Hard Drive Discs). Meanwhile, we have been thrown with terms like SATA, PCIe, and NVMe. But what is the difference between them?

What is SATA? 

SATA (Serial Advanced Technology Attachment) is a bus interface that can connect mass storage devices, including HDD and SSD, to a host bus adapter (HBA). SATA III (the third generation) is the mainstream model in industrial applications with a maximum speed of 0.6 GB/s. However, even with the same SATA interface, an SSD can still access higher transition speed and performance than an HDD.

What is PCIe ?

Another mainstream interface used in SSDs is PCIe (Peripheral Component Interconnect Express). PCIe is a modern bus interface that is much faster than SATA. Unlike SATA, which was invented based on the early specification of HDDs, the PCIe interface is developed based on SSD architecture. Hence, the PCIe interface enables SSDs to reach their higher potential in transition performance than SATA. The mainstream fourth-generation PCIe (PCIe Gen4) interface allows data transition speed of up to 32 GB/s with 16 channels, a great leap forward versus SATA at 0.6 GB/s with only one channel.

SATA and PCIe, which to choose?

Before getting into the competition, let's take a look at NVMe first.

NVMe (Non-volatile Memory Express) is a storage protocol for the PCIe interface. It allows modern SSDs to read and write at full speed by enabling flash memory to connect directly to the installed equipment via PCIe rather than through an intermediary like SATA. Hence, with PCIe interface and NVMe, SSDs can achieve lower latency, better data processing performance, and higher transition speed (up to 26 times with the latest PCIe Gen5) than the SATA.
SATA is not compliant with NVMe. This is because the mainstream protocol designed for SATA is AHCI. On the other hand, PCIe interfaces comply with both AHCI and NVMe protocols, but the former will limit the performance since AHCI is not built for PCIe. As a result, PCIe is usually suggested to come in hand with NVMe.

Well, so it seems that PCIe NVMe is the winner? 

Let's not jump to the conclusion so fast. The dilemma in the tech world still lies. High performance and speed are accompanied by high temperature, which can easily lead to overheating and, thus, questionable reliability. Therefore, choosing PCIe (NVMe) or SATA, high performance or high reliability, is the users’ choice. A hint is to make your choice based on your application’s needs. For HPC (high-performance computing), server, cloud computing, PCIe NVMe SSDs are recommended to help optimize performance and services. 

Although the mainstream interface in industry is still SATA, as the popularity of IoT, AI, cloud, and edge computing continues to grow, it is predicted that PCIe will gradually take over SATA in the future. To address the overheating issues following on the heels of data intensive workloads, Cervoz offers a comprehensive set of overheating solutions, which allow our customers to enjoy high performance and reliability in the same time.

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