Hard Drive Comparison - What Storage is Best for Your Small Business: SATA, SAS, or SSD?
Data has become the lifeblood of the small business world and is at the core of nearly every business decision made these days. It’s essential that small businesses obtain the right storage technology based not only on the volume and type of data they retain, but also on the frequency in which they retrieve it.
There are two hard drive technologies that small businesses must choose from: hard disk drives (HDDs) and solid-state drives (SSDs). Hard disk drives are dependent on mechanical parts. They have metal arms that read and write data across a spinning circular disc, which stores information. In contrast, Solid-state drives do not have any mechanical parts.
There are two primary types of HDDs: Serial ATA (SATA) and Serial Attached SCSI (SAS). Although similar, there are a few key differences. Below is a breakdown of each storage solution, its advantages, disadvantages, and primary uses to help small businesses select what’s best for their specific needs.
SATA drives are the most common storage type found within consumer and small business PCs. The “ATA” in “SATA” stands for Advanced Technology Attachment. It references the cable that SATA hard disk drives use to connect to a computer’s motherboard. It has two conductors for sending data, two for retrieving data, and a power cable, all in one wire.
Advantages of SATA
The primary benefits of SATA drives are cost and capacity. Compared to other drive types, SATA is cheaper per GB and there tends to be more capacity packed within a single drive. Its cost-effectiveness can be attributed primarily to the simplicity of its named connector.
Disadvantages of SATA
SATA drives have a few disadvantages when it comes to speed, connection and workload. While these drives store or “write” data rather quickly, they are slower when it comes to retrieving or “reading” data. The single data port and cable that gives the technology its name limits connection to a computer’s motherboard and nothing else. SATA is also designed to only be in use 8 hours per day, five days per week, limiting their use to typical business hours. They are not designed to handle workloads that are reading and writing 24/7/365.
When to use SATA
If cost and the ability to store lots of local data on your workers’ personal machines are your main considerations, then SATA is the best choice. Regardless of their limitations, SATA drives are well suited for most common uses. They’re ideal for file sharing, email, backup and archiving data that’s not retrieved frequently.
The “SCSI” in Serial Attached SCSI (SAS), pronounced “scuzzy”, stands for “Small Computer Systems Interface.” Like SATA, it has 2 conductors for sending data and 2 conductors for receiving data, but they are separated into 2 different data ports via cables. The separation of these data ports makes all the difference.
Advantages of SAS
The seperate cables allow SCSI to safeguard itself from data loss. SCSI uses RAID (Redundant Array of Independent Disks) to correct, read, or write errors much more effectively than SATA. Dividing the connectors into data ports, not only improves error correcting, it also enables drives to be connected to more than just a computer’s motherboard. With multiple data paths, SAS drives can additionally be connected to the motherboard and another storage device that has SAS connectors, including an array of different drives. This makes switching from one drive to another a lot easier.
SAS drives are designed to support robust applications that work nonstop. Because nonstop processing generates a lot of heat, SAS drives can also withstand higher temperatures. They are also faster. Where SATA drives can reach 7,200 revolutions per minute, SAS drives reach up to 15,000 revolutions per minute. Besides spinning quicker than SATA drives, SAS also uses a higher signal voltage that allows it to transfer data at twice the speed. Most importantly, SAS retrieves data just as fast as it stores it.
Lastly, SAS drives are more durable. SATAs have a Mean Time Before Failure (MTBF) of 700,000 hours, whereas SAS have an MTBF of 1.2M hours.
Disadvantages of SAS
Since the hardware within SAS drives is more complicated, they’re generally more expensive; however, SAS prices are slowly converging with SATA. Unfortunately, as you pack more capacity into a SAS drive, speed is sacrificed. This disadvantage is mitigated by the fact that multiple drives can be used in conjunction to form one cohesive, larger environment.
When to use SAS
Simply put, SAS is great for two purposes, servers and workstations. Any machines that are operational 24/7 or are disseminating robust amounts of data to multiple employees should be outfitted with SAS HDDs. SAS drives are also appropriate for graphically-intensive and processing-intensive work. Many creative professionals that require higher read/write speeds may already be familiar with using multiple hard drives. Using multiple SAS HDDs can provide the capacity they need, while retaining the superior speed their applications thrive on.
Rather than functioning on moving parts, SSDs use memory chips or caching devices, similar to those found in USB sticks. The more memory chips, the more capacity an SSD has. Just like HDDs, SSDs can come with SATA or SAS connectors, but the former limits the potential speed SDDs offer. Also, they can fit within standard hard drive slots, so they are a viable alternative to HDDs.
Advantages of SSDs
First off, SSD are a form of memory called non-volatile memory, making them more resistant to damage and higher performance. Since they don’t rely on a spinning disc to rotate to the correct location to read or write data, an SSD is considerably faster. When booting up an operating system from an HDD, it takes an average of 30-40 seconds. With SSDs, it takes only 10-13 seconds. The throughput of an SSD is about 550MB per second, where HDDs have a throughput of 125MB per second.
Not having moving parts not only boosts an SSD's speed making them more energy efficient, but it also elongates its life. The mean time between failures for SSDs is 2 million hours, which beats even a SAS HHD’s 1.2 million hours.
Disadvantages of SSDs
Historically, the storage density of SSDs was weaker than HDDs, but the ability to cram more GB in each drive has improved over the years. SSDs with more capacity are becoming more available, but they are more expensive than both SATA and SAS HHDs. Hands down, SSDs provide superior overall performance, but the equivalent amount of storage in an SSD compared to an HDD can be cost prohibitive.
When to use SSDs
Considering they’re still more expensive than HDD alternatives, SSDs should be reserved for storing high-frequency, immediate transactional data that must be written and read rapidly. This can include databases, CRMs, and bank transactions. Much like HDDs, SATA SSDs are typically used in PCs (even though it limits the speed) and SAS SSDs are found in servers, storage arrays, and workstations running workloads that require high availability, high input/output (IO), and low latency. For the most important data that’s called on often, SAS SSDs are worth the price.
There’s no need for a small business to pick one type of storage solution to solve all its needs. It’s best practice to purchase the optimal solution for each individual situation. Fortunately, most PCs allow for SATA and SAS drives, so it’s possible to install a mix of SSDs and HDDs. As SSDs become more affordable, it can be wise to install a computer’s operating system on a smaller SSD and store less critical files within an HHD.