Disk Drives

We finished all the periphery equipment outside the computer case.   It's now time to dive in and go inside as we get ready to build our computer.  Let's start with disk drives.

Disk drives use to come with Mb's of storage, that's megabytes, then the hard drive manufacturers started being able to make Gb, gigabytes, drives, and in the last year we have seen Western Digital come out with a 2TB, terabyte, drive.  Disk drives are one of the best bargains on the market as the price per byte (equivalent to one letter of text) has steadily declined.

Besides competition from each other for the biggest, most quiet, and fastest hard drive with the latest technology, the other thing driving  disk manufactures is the steadily declining price of solid-state storage. Solid state storage's big advantages are no moving parts so they are more reliable and they're fast.  Hard drive manufacturers have also increased their reliability over time and speed.  For now, solid state drives are still pricey, so will stick with hard drives for our system.

What do you look for in a hard drive? Manufacturer's have tried for years to come up with something unique to separate themselves from one another. We have the quietest, the most power efficient, the most reliable,the most storage, and the fastest hard drives.

The first three features are for system builders who build specialized computers. The quietest is used for ultra quiet computers. If you want to check how much noise the drive makes, drive specs come with a sound rating in db, decibels.  Go for the lowest db's. The most power efficient is used for people who are worried about how much power the comptuer wiill use.  How green are you? And the most reliable drives are used with servers that require a lot of drives and storage. They look for specs like mtbf, mean time between failure.


The last two features I mentioned are where we want to put our focus. The faster the disk drive the faster your system will seem to be. You want the fastest drive possible. By fast, I mean how fast can the disk read and write data to and from the computer's memory. The manufacturers have several ways to increase the transfer rate. They can spin the disk platters faster with higher revolutions per minute, rpm. They can add more disk platters and have the disk controller read from several platters at once, and you can add cache memory to save some of the most recent accesses and retrieve from cache. Retrieving from cache memory can be a good 30 times or more faster than directly  from the disk.  Despite all these techniques, it all boils down to transfer rate.  Today's technology feature Serial ATA, SATA, connectors and
transfer rates of 3Gb per second. This is what your looking for when you select your drive.  Get SATA drives for their high transfer rate.  SATA drives also have superior connector cables over the older IDE connectors.

The most storage is mostly a matter of how much you want to spend.  I highly recommend you buy two identical hard drives.  Just to put a number up in the air, I would say for a majority of users, two 300Gb drives is more than enough room for today's computer usage. You can get by with a lot less.  You use the extra drive for setting up a mirror drive, or a super fast back up of your key data. It also can be used for media storage of your music and DVDs.  Some server providers set up RAID configurations which helps protect data by duplicating your data across mulitple drives in different configurations, in which case, you may need even more than two drives.  If your a home  enthusiast, however, I'd just go with two disk drives.


As to which manufacturer, I think as long as I can remember, I have been partial to Western Digital hard drives, but there are many good hard drive manufacturers, so you can't go too wrong no matter which manufacturer you choose.

Comments are closed.