Physically, the most common SSD size is 2.5 inches – the same as a standard laptop hard drive (and therefore a straight swap). To fit one into the larger 3.5 inch drive bay of a PC you will need an adapter bracket – many SSDs come with one but, if not, they only cost a few dollars.
SSDs have a number of advantages over traditional hard drives, and just two disadvantages. We’ll review the advantages first:
Speed – The biggest single advantage. SSDs are typically 2-5 times quicker than a standard hard disk drive (HDD). SSD read/write speeds vary from 200 MB/s to 500+ MB/s whereas HDDs will struggle to achieve 150 MB/s.
What does that mean in practice? On a typical W7 computer, startup and shut down times will be halved with an SSD. E.g. if a standard W7 laptop takes 40 seconds to boot into Windows and 10 seconds to shut down, replacing the HDD with an SSD could decrease those times to just 20 seconds and 5 seconds respectively.
The faster speeds of an SSD can also make launching applications extremely quick – even huge applications like Photoshop (that normally take up to 10 seconds) will open almost instantly. Comments from buyers often refer to program launch times being almost instantaneous – and that they would never go back to an old HDD…
Example Video – SSD vs HDD
This video (not mine) is a perfect way to highlight the difference in speeds between the two drive types:
SSDs draw about 6 watts less power than HDDs – this is less important in a PC but in a laptop/netbook it could extend battery life by up to half an hour.
SSDs have no moving parts and therefore no vibration – just like a Flash Drive they are totally silent.
HDDs whirr, vibrate and click away – often loud enough to hear which can be annoying.
As SSDs have no moving parts and use less power, they produce very little heat – HDDs can reach temperatures up to 50 C degrees.
Lower temperatures help keep the computer cool and protect electronic components from heat related damage (which leads to shortened lifespans).
Fans will also need to spin less quickly which results in less noise – fans are often the noisiest part of a computer.
SSDs can typically withstand a shock up to 1500G whereas standard drives can only take about 350G.
As I see all too often in my computer repair business, if you drop a standard laptop onto the floor there is a good chance of damaging (or reducing the life of) the hard drive – even running upstairs with the laptop switched on can damage it…
This is far less of an issue with an SSD – although not recommended, a major collision is more likely to damage the screen or casing than the SSD. If you want a rugged laptop with optimal protection for your data, an SSD is a much better option.
In theory, both SSDs and HDDs have a ‘mean time between failure’ rate of around 2 million hours which equates to many years of continuous use.
In practice, I see many laptop HDDs failing after just a couple of years if the laptop has lived a hard life on the road – the better Shock Resistance (described above) means SSDs are more likely to outlast HDDs in laptops.
In PCs which are seldom moved, the lifespans should be similar.
Disadvantages of SSDs
Limited Storage Capacity
SSD capacities are typically 60 – 240 GB whereas standard hard drives are typically 320 – 1000+ GB.
[Larger SSDs are available but their prices are stratospheric]
This lack of storage capacity might be an issue if you want to store hundreds of GBs of data. Fortunately, in PCs it’s possible (in all except the very smallest) to add a second hard drive – e.g. use an SSD to store Windows and Programs but store data (pictures, videos etc) on a separate 1TB+ HDD.
Laptops usually only have space for a single drive so the limited capacity may be more of a deal breaker – but laptops are often used as portable devices, less likely to require storage of huge amounts of data.
Linked to storage capacity – SSDs are far more expensive than standard hard drives for the same capacity.
As an example, a 120 GB SDD costs about $100 – the same as a quality 640 GB HDD.
For technical reasons, it is advisable that the computer has a SATA controller with AHCI – and preferably a SATA 3 (6Gb-s) rather than SATA 2 (3Gb-s) interface to achieve the full 500+ MB/s speed potential.
New computers and those from the last couple of years are more likely to meet these requirements but do check first. In particular, XP does not include support for AHCI by default (although a manufacturer’s chipset driver might add it).
Are SSDs Suitable For Older Computers Too?
The costs/benefits make them more suited to newer Windows 7 computers but they could also make a big difference to older computers – check the requirements above and research thoroughly before buying.
Tom’s Hardware produced a useful in depth review of SSD performance in older computers which concluded that there are still useful gains to be made.
SSDs can greatly speed up a new (or slow) computer – if you can live with the restrictive storage capacities.
It may be worth retro-fitting an SSD into an existing computer but the easiest way to take advantage of an SSD is to buy a computer with one already fitted.
Big box stores are particularly bad at providing a choice of drive in new computers – small local computer shops are often more willing to tailor a system to meet your exact requirements.