5 Things You Should Consider When Buying An SSD
We explored the pros and cons of SSDs a few years ago. At the time, most users were put off SDDs because of high prices, limited storage capacities, and potential for compatibility issues. Most of those issues have cleared in recent times, so yes, you should get one!
That being said, there are a few points to consider before diving right in. Don’t go into it blindly. Stay educated so you can make the best decisions when purchasing your next SSD.
SSD prices have plummeted over the past few years. In 2010, the average price hovered around $3.00 per gigabyte, whereas in 2015 you can find SSDs for as low as $0.34 per gigabyte (as is the case with the Crucial BX100 500 GB for $169).
Relatively speaking, however, SSDs are still more expensive than traditional spinning hard drives, and this difference is not negligible. For example, a Western Digital Blue 1 TB can be bought for $53. Compared to the Samsung 850 EVO, the WD Blue is one-third of the price for twice the capacity.
So in terms of being economical, HDDs beat SSDs without question. If your budget is strapped, stick with an HDD. However, SSDs have never been cheaper than they are today and they’re quite affordable, so don’t be afraid to spend the cash.
If you do decide you’ll want an SSD, purchasing a larger capacity drive provides more value for money. For example, the Samsung 850 EVO 120 GB is $73 ($0.61 per GB). For an extra $33, you could more than double the storage capacity to 250 GB ($0.42 per GB). The $178 500 GB SSD offers the best value at $0.36 per GB. So by buying the 500 GB SSD, you’re only paying almost half the price per gigabyte!
Whenever you buy hardware, you have to look out for potential incompatibilities. The best SSD in the world is useless if you can’t mount it in your system, right? Fortunately, SSDs are pretty much standardized (for the most part) so you’ll be okay as long as you pay some semblance of attention.
Form Factor: Most modern SSDs come in a 2.5-inch form factor, which happens to be the standard size for laptop HDDs. Such a drive is unsuitable in desktop computers, which usually require a 3.5-inch form factor, but you can remedy that with an adapter like this SABRENT 2.5″-to-3.5″ Mounting Kit for $7.
It’s worth noting that there’s a newer form factor that’s gaining popularity: the M.2 standard (formerly called NGFF). These SSDs are tiny and thin, meant to fit into ultra-thin laptops and mini personal computers .
Z-Height: But just because you get an SSD with a 2.5-inch form factor doesn’t mean it’ll fit right into your laptop. You also have to make sure the z-height, or thickness, is small enough for your laptop body.
Typical z-heights are 9.5mm and 7mm, with modern SSDs leaning more towards the 7mm side. Consult your laptop’s manual or user guide to see which thicknesses are supported.
Interface: Consumer-grade SSDs pretty much all have a Serial ATA (SATA) interface, although whether you should get a 3 Gbps SATA or 6 Gbps SATA will depend on whether your computer can handle those speeds. Nowadays 6 Gbps drives are more common, but 3Gbps are often cheaper if you can find them.
[July 2019 Update] These days, you can also get SSDs with an PCIe interface. Unsure what to buy? Our PCIe vs. SATA guide helps you decide.
Noise: One benefit of an SSD over an HDD is that SSDs operate silently because they lack mechanical parts. If you want to move past the whirring of an HDD as it spins up and the chitter as it looks for files, then go for the SSD.
The main benefit of an SSD over an HDD — and the reason why so many people live by the SSD once they make the switch — is the fact that SSDs are significantly faster. With SSDs, computers boot up in seconds, programs launch almost instantaneously, and files are transfers up to 10 times faster.
Which is to say, even the worst SSDs are still miles ahead of HDDs in terms of performance. If speed is your only concern, then there’s no question: SSD wins every time.
That being said, not all SSDs are made equal. Consider these two options:
- the SanDisk Internal 120 GB ($52) which has a sequential read speed of 520 MB/s and a sequential write speed of 180 MB/s,
- the Silicon Power Velox V70 120 GB ($140) with a sequential read speed of 557 MB/s and a sequential write speed of 507 MB/s.
Maybe the difference of 37 MB/s while reading and 327 MB/s while writing isn’t important to you, in which case you should just go for the cheaper option. But if you honestly need every bit of speed, then you should be aware that it’s going to cost you (an extra $88 in the example above).
There’s an important distinction between the way SSDs and HDDs operate. While HDDs often have to deal with disk fragmentation , SDDs have a quirk of their own to worry about: garbage collection.
When data is written to an SSD, it’s written in chunks called pages. A group of pages is called a block. At any given time, the pages in a block could be all empty, all full, or a mixture of empty and full.
Due to the way SSDs are engineered, it’s not possible to overwrite existing data (which is possible in an HDD). Rather, in order to write new data to an occupied block, the entire block has to first be erased.
Furthermore, to prevent loss of data, whatever information existed on the block must first be moved elsewhere before the block can be erased. Once the data is moved and the block is erased, only then can new data be written to a previously-occupied block.
This process, called garbage collection, requires empty space to function properly. If you don’t have enough space available, then the garbage collection process loses efficiency and slows down. This is one reason why an SSD’s performance degrades over time: it fills up too much.
To keep the garbage collection going at peak efficiency, traditional advice is aim to keep 20 to 30 percent of your drive empty. For a 250 GB drive, that means you should only use up to 200 GB max.
You should also enable TRIM in your operating system.
The last thing to consider is how long the SSD with last you. In our comparison of storage drive lifespans , it was clear that about 74 percent of hard drives survived beyond their fourth year. How do SSDs compare?
Unlike HDDs, SSDs have no moving parts — which is great for quiet operation, and it also means there are no parts to wear out. Hence, mechanical failure isn’t something that should concern you.
The downside, however, is that SSDs are more prone to power failure. Loss of electricity while the drive is running could result in data corruption or even full-blown device failure. Learn the effects that electrical anomalies can have on your computer and how to prevent them .
In addition, the memory blocks in an SSD have a limited number of writes. If you’re constantly writing data to the SSD (on the order of gigabytes per day), then it’s possible for the drive to lose the ability to write any more data (though reading would still be possible).
The expected lifespan of an SSD is between 5 and 7 years, which is the average point of failure. With every year that passes beyond this point, the chance of drive failure increases.
Are SSDs Right For You?
If you’re on a tight budget, don’t care about speed, or prioritize data reliability above all else, then you should stick with a traditional spinning hard disk drive. For everyone else, it’s about time to move onto SSDs if you haven’t already.
Are you making the switch to SSDs? Tell us about it in the comments! Did we miss any important points? Let us know below. We’d love to hear from you.