Best SSD for Server Review

By: Bohdan Chub | 21.01.2021, 14:03

In the days of HDDs, choosing a drive was simply a matter of capacity, RPM speed, and manufacturer. With SSDs, it is much more complicated, especially if it will be used in a server to process important data. The wrong interface can become a bottleneck for the entire system, limiting the performance of your applications. And a model with a low endurance rating can fail after only a couple of months of use. To save you time, we've studied the offerings on the market and compiled the best server SSDs. In this guide, you'll also find out what features you should check for in the first place.

Best Choice
WD Gold SN600 WD Gold SN600
WD has fully embraced high-performance NVMe Flash technology to give your server an efficiency boost. The WD Gold SN600 SSD delivers speeds up to 3100 MB/s and is available in large capacities up to 7.86 terabytes. That's enough for most usage scenarios. It's reliable and built to handle power loss emergencies, plus it keeps your data safe and sound. Highly recommended!
Read Verified Customer Reviews

5 Best SSDs for Server – Overview & Rating

Author's Choice WD Gold SN600 review WD Gold SN600
  • Capacities: 960GB - 7.86TB; Form Factor: U.2
  • Sequential Read/Write (Up to): 3100 / 1800 MB/s
  • Interface: PCIe 3.1 x4 / NVMe; Endurance (DWPD): 0.8
Check Price
Check Price
People's Choice Intel Optane SSD 905P review Intel Optane SSD 905P
  • Capacities: 380GB - 1.5TB; Form Factor: M.2, U.2, AIC
  • Sequential Read/Write (Up to): 2600 / 2200 MB/s
  • Interface: PCIe Gen 3.1 x4; Endurance (DWPD): 10
Check Price
Check Price
Premium Choice Micron 9300 Max review Micron 9300 Max
  • Capacities: 3.2TB - 12.8TB; Form Factor: U.2
  • Sequential Read/Write (Up to): 3500 / 3500 MB/s
  • Interface: PCIe 3.0 x4; Endurance (DWPD): 1
Check Price
Check Price
Best Budget Kingston DC500R review Kingston DC500R
  • Capacities: 480GB - 7.68TB; Form Factor: 2.5"
  • Sequential Read/Write (Up to): 555 / 525 MB/s
  • Interface: SATA 3 (6Gb/s); Endurance (DWPD): 0.5
Check Price
Check Price
Best SAS SSD Seagate Nytro 3531 review Seagate Nytro 3531
  • Capacities: 800GB - 6.4TB; Form Factor: 2.5"
  • Sequential Read/Write (Up to): 2200 / 1550 MB/s
  • Interface: SAS 12Gb/s; Endurance (DWPD): 3
Check Price
Check Price

Detailed Overview

Author's Choice

WD Gold SN600 WD Gold SN600
  • Capacities: 960GB - 7.86TB; Form Factor: U.2
  • Sequential Read/Write (Up to): 3100 / 1800 MB/s
  • Interface: PCIe 3.1 x4 / NVMe; Endurance (DWPD): 0.8
Check Price

Thanks to high data transfer speeds, NVMe SSDs are used in servers more and more. The WD Gold SN600 can read at up to 3,100 MB/s and write at 2,000 MB/s. While actual numbers vary by capacity, even the base model will be at least twice as fast as a SATA drive. This series is actually a rebranding of the Ultrastar DC SN640 product line. The new SSDs use the same technology and the 96-layer BICS4 3D TLC NAND flash memory. The drive has power loss protection and supports secure data erase. Considering the 0.8 DWPD endurance, the SN600 will not be suitable for extreme write-intensive applications like cache storage. However, it is a great option for mixed and read-centric workloads.

Pros:

  • High data transfer speeds
  • Great price to performance ratio
  • Advanced security features

Cons:

  • Higher than average idle power consumption

People's Choice

Intel Optane SSD 905P Intel Optane SSD 905P
  • Capacities: 380GB - 1.5TB; Form Factor: M.2, U.2, AIC
  • Sequential Read/Write (Up to): 2600 / 2200 MB/s
  • Interface: PCIe Gen 3.1 x4; Endurance (DWPD): 10
Check Price

Intel Optane SSDs with 3D XPoint technology are remarkably durable. They can write tens of petabytes of data throughout their lifespan. By comparison, most typical SSDs have a lifespan measured in terabytes. Furthermore, Optane devices are exceptionally good at handling random memory requests, producing up to 575,000/550000 IOPS for reads and writes. The Optane SSD 905P delivers high quality of service and remains responsive during concurrent I/O operations. If you run write-heavy workloads, this is an excellent choice. The series consists of three form factors (add-in card, U.2, and M.2), though storage capacity options are limited. Intel also has a separate Optane range for data centers with even higher DWPD and enhanced power loss protection, but they cost significantly more.

Pros:

  • Best in class random read and write performance
  • Outstanding endurance rating
  • Available in multiple form factors

Cons:

  • Low storage capacities

Premium Choice

Micron 9300 Max Micron 9300 Max
  • Capacities: 3.2TB - 12.8TB; Form Factor: U.2
  • Sequential Read/Write (Up to): 3500 / 3500 MB/s
  • Interface: PCIe 3.0 x4; Endurance (DWPD): 1
Check Price

The Micron 9300 family is represented by the Pro and Max versions. They are based on the same hardware, but the Max version has more space reserved for overprovisioning. This gave higher random write speeds. The Micron 9300 Max provides unmatched performance at high queue depths, topping its closest competitors. Sequential read and write speeds of up to 3500 MB/s can be achieved, near the four-lane PCIe 3.0 limit. The drive delivers a full enterprise feature set. For more efficient use of the storage, administrators can define up to 32 namespaces. With that, a single device will appear as multiple logical SSDs, allowing for more parallel sessions. The drives are designed to write from 18.6 to 74.7 petabytes of data.

Pros:

  • Versatile and works well for almost any type of server
  • Multiple namespaces support
  • High capacities of up to 15.36TB

Cons:

  • High power consumption (which is actually usual for the large capacity drives)

Best Budget

Kingston DC500R Kingston DC500R
  • Capacities: 480GB - 7.68TB; Form Factor: 2.5"
  • Sequential Read/Write (Up to): 555 / 525 MB/s
  • Interface: SATA 3 (6Gb/s); Endurance (DWPD): 0.5
Check Price

The Kingston DC500R is designed for read-centric applications, as indicated by the "R" in the name. It is the most affordable model of the range, which is equipped with capacitors for protection against accidental power loss. Thus, the risk of data loss is significantly reduced. The SATA interface limits the maximum read and write speeds however the DC500R is compatible with most existing server platforms. The metal casing helps dissipate heat, preventing the controller from overheating. The Kingston SSD Manager utility lets you not only monitor the health of the drive, but also configure the over-provisioning area. By slightly reducing the space available to the user, administrators can improve the performance and increase the lifespan of the drive. If your server needs to handle a lot of write operations, it is worth paying attention to the top-of-the-line Kingston DC500M with a DWPD rating of 1.3.

Pros:

  • Good performance for the price
  • Very competitive cost per gigabyte
  • Available at high capacities

Cons:

  • Latencies under load are higher than desirable

Best SAS SSD

Seagate Nytro 3531 Seagate Nytro 3531
  • Capacities: 800GB - 6.4TB; Form Factor: 2.5"
  • Sequential Read/Write (Up to): 2200 / 1550 MB/s
  • Interface: SAS 12Gb/s; Endurance (DWPD): 3
Check Price

Modern NVMe SSDs cannot be directly connected to SAS-based hardware. That's why it's too early to dismiss SAS drives. The Seagate Nytro 3531 series is designed for demanding enterprise applications and to reduce the total cost of ownership. The high-capacity models support dual-port functionality, allowing them to read data at 2200 MB/s and write at 1550 MB/s (1000 MB/s for the basic 800GB version). Another advantage is endurance: the Nytro 3531 can be fully rewritten up to three times a day for its entire lifespan. The drive is suitable for write-intensive workloads, such as processing of time-critical online transactions (OLTP), server virtualization, and email services.

Pros:

  • Fast performance
  • Solid endurance rating

Cons:

  • High cost per gigabyte

Buyer's Guide

How to choose a server SSD

We have already mentioned interfaces, endurance and performance in different scenarios. Now let's talk about it all in more detail. When choosing an SSD for a server, you should consider the following aspects:

Form Factor

The flash memory chips themselves don't take up much space, which allows SSDs to come in different shapes and sizes depending on user needs. The form factor determines the shape and size of the drive, and the most common ones are:

• 2.5" (or U.2)

2.5" or U.2 when it comes to NVMe, also known as small form factor (SFF). All drives are of standard length and width. The height ranges from 7 to 15mm depending on the capacity and cooling solution.

• Add-in card (AIC)

Add-in card (AIC), sometimes referred to as HHHL (half height, half length). An SSD as an add-in card is plugged directly into a PCIe slot on the motherboard. This connection utilizes more PCI Express lanes and the larger size of the AIC results in more efficient heat spreading. This increases maximum possible performance, but the drive is not hot-swappable.

• M.2

M.2 is a popular SSD form factor for laptops, also used in server hardware. However, there are usually only one or two slots on the board. Small stick shaped drives can be used for operating system loading or caching.

Interface

The interface or logical protocol determines how the SSD communicates with the CPU. Drives in different form factors can use the same interface, in servers are usually found:

• SATA

SATA is popular in the lower price segment. SATA SSDs typically have data transfer rates of less than 560 MB/s for sequential operations. The interface is the main performance limiter and the reason for the high latency, so more advanced technologies are used for demanding applications.

• SAS

SAS is the established standard for enterprise storage. The interface has gained popularity for its scalability and higher bandwidth. For example, 12Gb/s SAS provides up to 1GB/s on each of the two links. The dual port feature allows you to increase system fault tolerance by connecting one drive to two servers (if one of them fails, access to data will remain). But SAS drives require a special host bus adapter (HBA) or RAID controller. SAS interface can take a SATA drive, but not vice versa.

• NVMe

With an NVMe interface, the SSD is connected to the PCIe bus, which is either directly connected to the CPU or through the chipset. This significantly reduces latencies (up to a few microseconds), and data transfer speeds are limited by the characteristics of the memory itself.

When selecting an NVMe SSD, consider the supported version of the PCI Express standard. PCIe 3.0 provides up to 1 GB/s per lane or 4 GB/s for a "x4 Gen 3" slot. The next generation PCIe 4.0 doubles this speed.

Types of Flash Memory

SSDs write information on flash memory chips, also known as NAND. When SSDs first appeared, each cell could only hold one bit (0 or 1). SLC (Single-Level Cell) memory offered high data transfer rates, but low density and expensive manufacturing gave rise to other technologies. Sophisticated algorithms allow different levels of cell charge, which will correspond to a specific bit sequence. The downside of this approach is reduced durability. Each cell has a lifespan, and the more bits of information it stores, the more often it will be overwritten.

The following types of memory can be found in modern SSDs:

  • MLC (Multi-Layer Cell). Each cell stores two bits of information. The advantage of MLC memory is high speed and reliability, but it is used less and less often because of high cost.
  • TLC (Triple-Level Cell) is the most widely used type of memory. Compared to MLC it will have slower write speed and shorter lifespan. But TLC helped to make SSD more affordable.
  • QLC (Quad-Level Cell) is just starting to conquer the market. Because of the low endurance QLC memory is only applicable for consumer SSDs so far.

Apart from that there are Intel Optane drives with 3D XPoint memory. They use a crosspoint structure to address individual cells which in turn store only one bit of data. Advantages of the technology include speed (although faster NVMe SSDs have already appeared) and endurance. However, the high prices are still a big concern.

Performance

Real-world scenarios involve mixed loads, so benchmarks will not give you the overall picture. However, the performance of a drive is typically measured by the following metrics:

• IOPS

IOPS - the number of input/output operations (I/O) an SSD can handle in one second. This is stated in relation to the data block size (usually 4 KB), separately for read and write operations. Enterprise class drive manufacturers sometimes quote mixed IOPS (70/30 read/write).

• Throughput

Sequential read and write throughput of an SSD. Measured in megabytes per second (MB/s) or gigabytes per second (GB/s).

• Latency

Latency is the time interval between sending a request by a running application and receiving a response, whether it is a write confirmation or read data. Latency is measured in microseconds, and grows as the queue depth (i.e. the number of simultaneous requests) increases.

• Quality of Service (QoS)

Quality of Service (QoS) reflects the stability and predictability of drive latency. It must meet a specified level of service (99.9%, 99.99%, or 99.999%). For example, if the latency with 99.999% quality of service is 20 ms, then 99.999% of the I/O operations will complete in 20 ms or less.

Endurance and power fails protection

The expected life of a drive is expressed in Drive Writes per Day (DWPD) or Terabytes Written (TBW). This is the amount of data the device is guaranteed to write before it fails. You can calculate one from the other. For example:

TBW = DWPD * Warranty in years * 365 * Capacity in TB

It is quite possible that a high-capacity drive with a lower DWPD can write more data. You can also extend the life of the drive by increasing the overprovisioning area (if possible) to have more spare memory cells to replace those that are worn out. In any case, an ordinary consumer-grade SSD has a relatively low endurance rating. For servers, it is recommended to use the best enterprise SSD that fits your budget.

Another advantage of specialized SSDs is protection against power loss. For this purpose, additional capacitors are installed on the board, the charge in which is enough to carry out all unfinished write operations.

It is noteworthy that the consumer series Intel Optane 905P has no capacitors, but we still decided to add it to the list. Since the new generation drive does not use DRAM caching (write confirmation is sent when the data is already in memory), the risk of failure is extremely low. Although if the budget allows, you can choose Optane products for data centers with "Enhanced power-loss data protection" for more reliability.

You may also like