August 27, 2010

Between a rock and a hard drive

Autumn is just around the corner, the season with the most spectacular changes. And with the change in seasons you might be considering a change in computers. It’s a great time to buy; after all, back-to-school specials abound and options appear to be endless.

Among those multitudes of options that are now being offered on many brands of desktop and laptop computers is the choice between a standard magnetic media hard drive (HDD) and a solid-state hard drive (SSD).

The first and most obvious difference between the two is, without question, price. If you’ve looked into purchasing a new unit with a SSD, you were probably more than a bit sticker-shocked. HDDs currently run from about $.06 to $.16 per gigabyte, whereas SSDs will run in the neighborhood of $2.50 to $3 per gigabyte. Maybe it’s just that you get what you pay for, but at our current position in space and time, it is necessary to shed a little more light on the differences.

The HDD has been with us pretty much since the PC revolution started in the last millennium. A typical HDD is really nothing more than a series of two to five CD-like magnetic disks called platters and an arm that looks like the stylus arm of a phonograph (from back when turntables actually played vinyl LPs). As the platters inside the drive spin, the arm positions itself to read and/or write data to the platters. This has been a very efficient and effective method for storing and retrieving data, but it isn’t without a few shortcomings.

Almost all of the components directly involved with handling data inside the HDD move, and when things move you have power usage, heat and, eventually, mechanical failure. Power usage is negligible and heat is manageable, but failure is no joke – and all mechanical drives will fail someday. The trouble is you never really know when that is going to happen. If you’ve ever had a hard drive fail mechanically, you know just how devastating this can be.

Startup and seek times are also considered negative factors because parts of the HDD actually have to move through physical time and space, creating what is known as latency – the time it takes to request the data and then retrieve and display it. Most users don’t really see this as a negative simply because startup and seek times have always been part of the computing experience.

No moving parts

SSDs, on the other hand, have no moving parts, hence the term “solid state.” This means they greatly reduce the risk of mechanical failure, they are usually silent, and users enjoy a faster seek time and less latency because there are no mechanical delays. SSD access times are less than half a millisecond, where an HDD has an average access time closer to 12 milliseconds. While that seems like a large difference from a mathematical standpoint, most users say they really don’t notice the increase in speed until they switch back to a HDD.

SSDs also use considerably less power than the standard HDD and therefore become ideal components for laptops and mobile devices that rely on battery power. SSDs are, in many aspects, very similar to a usb thumb or flash drive – they are made up of an array of tiny transistors called memory cells that store the data.

Faster response times, and the illusion of a more stable and secure method of storing data might lead you to think that the SSD is without question, the way to go. But before you go shelling out the extra bucks, there are a few things to take in consideration.

Although capacity is predicted to increase within the near future, at the time of this writing, you probably aren’t going to find a SSD larger than 250GB. There are actually a few manufacturers that have 1TB drives on the market, but they are priced at a point that makes them all but prohibitive for the general consumer. These drives are targeted toward enterprise and industrial applications. If you think you can get by with 250GB, which is small by today’s storage standards, be prepared to pay; a search for similar sized drives brings back prices in the $800 to $1,000 price range, or as I like to say, “Uh … way too much”.

Another important aspect is that even though an SSD has no moving parts, it still has a limited lifetime. Those little transistors have a finite number of program-erase (P/E) cycles, where data is written and removed from them. One thing to note is that P/E cycles apply only to writing data; reading data that is already written appears to have infinite reads, so even though you can’t write anymore data to the drive, you shouldn’t have any trouble retrieving the data that is already there.

Depending on the quality of the product and the drive’s overall storage capacity, ratings can be found anywhere between 5,000 to 1 million P/E cycles. The smaller the capacity of the SSD, the faster the P/E cycles get used up per cell, which means a 30GB SSD will die much faster than one with a 120GB capacity. However understand that, in order for the SSD to die completely, each cell has to be dead. Before then, writing capacity will simply decline. Suddenly 30GB becomes 29.8GB, slowly dying over time.

I have to say, I’m intrigued by the SSD and have no doubts that within the next few years HDDs will be relegated to the annals of computer history. But I’m not quite ready to make the jump myself. I want lots of space and I want that space to be as affordable as I can get it. I will sacrifice speed and the risk of lost data for that.

Adoption of the technology and increases in capacity should bring about lower pricing in the near future; I can wait a bit longer for a larger, cheaper SSD.

Until next time Reputo. Lego. Diligo.

Michael Wailes is an Interactive Developer at Burns Marketing and Communications in Johnstown. If you have questions or would like to suggest a topic for a future Geek Chic column, e-mail him at news@ncbr.com.

Autumn is just around the corner, the season with the most spectacular changes. And with the change in seasons you might be considering a change in computers. It’s a great time to buy; after all, back-to-school specials abound and options appear to be endless.

Among those multitudes of options that are now being offered on many brands of desktop and laptop computers is the choice between a standard magnetic media hard drive (HDD) and a solid-state hard drive (SSD).

The first and most obvious difference between the two is, without question, price. If you’ve looked into purchasing a new unit with…

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