Data Storage

          Ever heard of solid state drives (SSD)? Chances are you probably did, but do not really know what they are. I can imagine you scratching your head saying: " Aren't they just about the same with hard disk drives?" There’s been a lot of hype lately about solid state hard drives as well as a lot of computers offering them as an option. What exactly are solid state hard drives, what are their pros and cons over standard mechanical hard disk drives? In this mini tip, we’ll take a look at these drives that seems to have mysteriously appeared in the market, especially with Apple.

          So what are they exactly? Quite simply, they are hard drives that use memory chip instead of a spinning platter that a standard mechanical hard disk drives would use. 


          There are some very obvious advantages over a standard mechanical hard drive. First off, they’re solid state! That is, there are no moving parts, no spinning platter, no actuator arm, no motor, no nothing – just a bank of memory chips – this means that there is a much higher degree of mechanical reliability. Because they’re just a bank of chips, there is no time used to spin up thehard drive, it is just up and ready as soon as it is powered. Also, because there is no time spent for the actuator arm to read information off the platter, solid state drives can read much, much faster than a standard mechanical hard drive. 


           Another nice advantage is because there is no spinning motor, there is no noise generated by the solid state drive (though some may incorporate a small cooling fan, that is nothing compared to the noise generated by a disc spinning at 7200 RPM). In addition, file fragmentation has very little impact on a solid state drive because of the very constant seek time performance of this type of drives. Solid state drives are also able to withstand shock and temperature extremes better than a mechanical drive, an important consideration if ever dropped.


            The major disadvantage? They wear out – or more to the point, the individual bits after a while can’t be erased and written to again. Flash memory quite simply has a limited number of times that information can be written to a location (a bit). Most consumer drives on the market today can handle about 10,000 writes to a bit. Once that spot is used up, it can never be used again. The good news is that there are a variety of techniques that engineers have developed to help combat this issue. The first thing is better flash chips. The chips used today are much better then the chips used in the first solid state drives that appeared a while ago on the enterprise level. Also, some drives employ extra memory chips to replace the bits that may go out. Many also employ wear leveling techniques that help wear the chips evenly. Another plus is that drives are larger and larger, so there are many of these bits to go around. Unfortunately, there doesn’t seem to be any consensus on what this means in practical, real world terms. How long will a drive last used with a standard operating systems, in a standard computer? Different sites have different answers, some saying as little as a year, while others up to five years (with normal usage). Another point to consider is that solid state drives don’t have the capacity of mechanical drives, though the gap is rapidly closing. This means that you can pay the same amount of money for a 32GB solid state drive that you may be paying for a 320GB mechanical drive.

Who Will Benefit Most From Solid-State Drives?

Because they can access and read data very quickly, you'll find that the biggest visible advantages of an SSD are fast boot-ups and application starts. Thus, they are the most useful if you're the type of person that likes to launch a lot of applications, or launch certain slow-loading applications such as Adobe Photoshop. In addition, if you find yourself restarting your computer a lot (perhaps because you dual-boot), you'll be happy with the decreased boot time of an SSD, lessening the time you spend waiting for your computer to start up and increasing the time you can spend working.


On the other hand, if you tend to just use your computer to check email on the web or write documents, you won't notice the benefits of an SSD as much. Web sites won't load any faster, and if you're only launching your browser and one or two other applications, it probably isn't worth the upgrade to have them launch a few seconds faster.


In the video below is a series of tests to compare how must faster SSDs are to compare to traditional magnetic hard drives.