SSD vs. HDD | Computing
Solid-state drives (SSD) and hard disk drives (HDD) are the two main storage solutions available to consumers and they each have their benefits. That makes them quite specialist for different tasks, but if you asked us to pick one over the other for your main system, our recommendation would be clear. The battle of SSD vs. HDD was won long ago.
The best SSDs are far faster than their HDD counterparts, and though they lose out when it comes to overall storage size, their pricing isn’t too distinct these days to warrant a hard drive instead.
It isn’t difficult to find hard drives with several terabytes worth of storage and they are getting bigger all the time, without too much of an increase in cost to the consumer. In contrast, SSDs tend to be much smaller and become prohibitively expensive over 2TB.
When it comes to storage space though, hard drives have a distinct advantage and likely will do for the foreseeable future. If you want to store something long-term or store large files and folders, hard drives are the way to go, but that is one of the only areas where hard drives still hold sway.
Speed, form factor, and durability
Drive “speed” is predominantly focused on how fast they can read and write data. For HDDs, the speed at which the platters spin helps determine the read/write times. When accessing a file, the “read” part of the read/write head notes the positioning of the magnetic sections as it flies over the spinning platters. As long as the file being read was written sequentially, the HDD will read it quickly. However, as the disc becomes crowded with data, it’s easy for a file to be written across multiple sections. This is called “fragmenting” and leads to files taking longer to read.
With SSDs, fragmentation is not an issue. Files can be written sporadically across the cells — and in fact are designed to do so — with little impact on read/times, as each cell is accessed simultaneously. This easy, simultaneous access to each cell means files are read at incredibly fast speeds — far faster than an HDD can achieve, regardless of fragmentation. That’s why SSDs can make a system feel snappy, because their ability to access data across the entire drive (random access) is so much faster.
This faster read speed comes with a catch. SSD cells can wear out over time. They push electrons through a gate to set its state, which wears on the cell and over time reduces its performance time until the SSD wears out. That said, the time it would take in order for this to happen for most users is quite long; one would likely upgrade their SSD due to either obsolescence or a desire for more storage space before a normal SSD would fail. There are also technologies like TRIM which help keep SSDs from degrading too quickly.
That said, hard drives are much more vulnerable to physical damage due to their use of mechanical parts. If one were to drop a laptop with an HDD, there is a high likelihood that all those moving parts will collide, resulting in potential data loss and even destructive physical damage that could kill the HDD outright. SSDs have no moving parts, so they can better survive the rigors we impose upon our portable devices and laptops.
Another thing to be mindful of is the form factor of these devices. HDDs are almost always a 3.5-inch or 2.5-inch disk, while SSDs are spreading out into a variety of shapes and sizes. The most common is still the 2.5-inch drive, but smaller SSDs built on form factors like M.2 and PCIe are becoming increasingly common too. They are more expensive than their SATA III counterparts, but are much smaller and increasingly offer the fastest storage speeds available.
Although prices have been coming down for years, SSDs are still more expensive per gigabyte than hard drives. For similar amounts of storage, you could end up paying nearly twice as much for an SSD than an HDD — even more so at higher capacities.
While you’re paying higher prices for less space with an SSD, you’re investing in a faster, more efficient, and far more durable data storage overall. If you’re building a system with speed, power needs, or portability in mind, then an SSD is going to be the better choice. In most desktops, adding another hard drive is easy and cheap, so it’s a good upgrade down the road if you need more storage space. Having a separate data drive also allows you to update or reinstall your operating system with minimal effort.
As SSD prices drop to bargain prices, we are finding fewer reasons to opt for HDDs in the majority of systems. For $70, there are brand-name 240GB SSDs available, just $20 more than the cheapest 1TB HDD. For that $20, even casual users will notice a drastic improvement in boot-up time, data access, and general system snappiness. We expect new systems to include an SSD — or at least a hybrid drive.
Hybrid drives, externals, and the final word
Hybrid drives offer a middle ground between the benefits of SSDs and HDDs. They combine an HDD and SSD into one device. There are a couple different versions of this sort of technology.
First, there are the SSHDs — or solid-state hybrid drives. These drives are full-sized HDDs (often around one or two terabytes) that come equipped with an extra cache of SSD NAND memory (usually a few GBs worth). SSHDs work by learning which files you use most often and writing them to the quickly accessible SSD section of memory. All other files are stored on the HDD’s spinning disc. While an SSHD won’t give you the durability and lower power needs of an SSD, they should still offer an appreciable uptick in speed for certain processes.
You can find SSHDs that can fit a 2.5-inch slot as well as 3.5-inch options. In addition to these two hybrids, which are good options for those with space for only one drive, one could also opt to buy multiple separate drives depending on their configuration and available mounting space.
In addition to these other choices, there is also the option of using a drive as an external storage device. There are drives manufactured specifically for that purpose — however, virtually any drive that can be mounted in a PC can be inserted into an external housing kit and connected to a PC via USB. The device will function as a drive normally would but can be carried with you, so you can access your stored files with any PC or laptop.
As the storage landscape shifts rapidly, SSDs are going to become much more prevalent than HDDs. We don’t recommend buying a system that only has an HDD in it, as you miss out on a much snappier PC usage experience. The price difference will be well worth it, if there is one at all, and the result is noticeable every time you turn it on.