Hard Drives

You won’t get very far these days without a sizeable hard drive.  A hard drive is one of the key components in a computer system in that it represents a data bottleneck.  The tradeoff between being able to store lots of information (permanently) is that this ’physical’ system of plates and scanning heads is about 60,000 times slower than RAM storage.  However, the hard drive is where all the data in your system is stored.  The operating system, all of your programs, and your music/movies are all housed in the hard drive. 

Back in the day, I remember having a 100 MB hard drive was a big deal.  Now, 100 GB is the standard, which represents a 10x jump in size requirement over a decade.  Considering that the average game is about 700 MB to 4 GB in size, and that applications and downloads can slowly chip away at your hard drive, having a big one in excess of 60 GB is definitely a good idea.  But wait!  Size isn’t the only thing that matters here.  Other specs like RPM speed, buffer size, and transfer rate define how well the hard drive will perform, regardless of how big it is.  The higher the RPM, the faster you will be able to transfer data and seek programs.  Most hard disks these days are rated at 7200 RPM, but there are some out there that go even faster (but they’re more expensive).  When it comes to buffer sizes and transfer speeds, let’s consider the three industry standards for personal computing:

Old School IDE: the Regular ATA Drive

All computers come with support for a regular IDE drive.  These are the most common hard drives with the flat ribbon cable data connector.  There’s no reason why you shouldn’t be using one of these unless you’re a performance nut.  IDE drives come in different flavors of transfer rate.  The specs that define an IDE drive are the UDMA rating and its buffer size.  The UDMA rating lists the drive’s transfer speed.  Most modern motherboards can support UDMA 133, which can handle 133 MB/s of data transfer.  Furthermore, the buffer size for IDE drives is either 2 MB or 8 MB.  It’s been found by many benchmarkers around the world that a regular IDE hard drive with 8 MB buffer is competitive to the other higher-end models in performance, but comparatively cheaper.

S-ATA: Next Generation

A new standard developed by over 80 companies is the serial-ATA drive, known as SATA.  This new standard promises easier installation and configuration, along with transfer rates up to 150 MB/s.  Considering that UDMA 133 drives with 8 MB buffers can come close to these specifications, there’s no real point in getting a SATA drive right now because you won’t be able to mix the two types within the same system.

IDE-RAID

Once a niche market for servers, the Redundant Array of Independent Disks (RAID) was an old standard created to allow servers to connect many smaller hard drives to form a single large storage space.  Transfer rates for RAID are incredibly fast because two or more hard disks are used at the same time for the exact same operation.  If you want a RAID setup, you’ll have to buy a RAID controller.  They’re not that expensive though, and if you want to hook up two 120 GB IDE drives to a cheap RAID controller it won’t run you more than $400.  However, I’m a bit suspicious of why you’d ever need this.  Considering that a 160 GB hard drive with an 8 MB cache goes for a quarter of this price, I’m hard pressed to figure out why you’d need such high storage amounts and transfer speeds.  Unless you’re doing a lot of crazy stuff like ripping and encoding DVD movies, there’s just no need for these kinds of numbers!