From the boot up of Windows to the need of extra texture memory for our 3D games the hard drive has always and forever will be, your friend. "Ops that’s Star Trek". Hehe But you know what I mean. The hard drive is one of the hardest working parts to our computer and yet it’s also the least thought about things for us gamers. I mean we worry about computer fans more then we do about our hard drives. So let’s take a good look at what goes on in the hard drive.  

The hard disk is a metal platter coated with magnetic oxide that can be magnetized to represent data. Magnetic disk storage are basically diskettes that are based on a technology of representing data as magnetized space on the disk, with the magnetized spot representing a 1bit and the absence of a magnetized spot representing a 0bit. So that means in order to read data from the disk the hard drive would have to convert the magnetized data to electrical impulses that can be read by the brains of the computer the CPU. Now writing also uses the same steps but it just basically does it in opposite order. As you all know hard disk comes in many different sizes these days and in many cases the bigger ones use several disks to produce a disk pack which can be put into one hard drive case. Example: just think about a 10Gb drive that has 5 disks which means that each disk has a storage capacity of 2GB(look at the very first picture at the top of this page to see what a disk pack looks like). Although it is a good idea of doing things a disk pack rotates, reads and writes at the same time which means only one disk is being used at any given time. The device that is being used to read and write the data is called an access arm which moves the head into where ever is it needed, so the access time is a estimated time it takes for the head to find it’s location on the drive to read or write the needed data. The average access times of hard drives these days is either 10 to 8ms for your average EIDE hard drives and about 7 to 5ms for your high end SCSI drives. Remember now the access time is the speed of which the head can move to the right location on the drive. So the only thing that remains is the disk itself, now that’s where the rotation speed comes into effect. You’ve heard about 5400rpm, 7200rpm and 10000rpm for your high end SCSI drives. So what does that all mean? Well the faster the disk can spin the faster the part that needs to be read on the drive can be moved to the head.  

As you can see from the chart that the Disk isn’t slowing the hard drive as much as the head is with it comes to finding data.

RAID which stands for redundant array of independent disks. Any ways RAID is when you use several hard drives that work together as a unit. The easiest RAID is called Data Mirroring (RAID level 1) which is in simplest terms a really good backup system. What happens is that what ever data that is being changed on one drive is also changed on other drives which means that you’ll have more then one drive that has the same data. Now the upside to doing this is that if one drive crashes you’ll still have your other drive or drives to use. Now although this is a good idea it really shouldn’t be used unless your running a server or working with very important data at all times. But there is a down side to this and that is since your computer has to work harder to write both or more drives it would slow your computer down and another thing is that you might want to get more then one SCSI controller (or a SCSI controller that is multi-channeled) for maximum performance. Now higher level RAID takes a different approach called Data Striping which means the data is spread across two or more drives in the computer with one disk solely as a check disk to keep track of where the data goes on in the other drives (for really high end RAID setup only) which means that loading and reading times will be a lot faster.

Solid State Drives

Well this is where I believe the future is for hard drives. The Solid State drive technology is basically a ton of Flash Ram which acts as a hard drive and since it’s made out of Flash Ram the data that you’ve stored will remain active even when the computer is turned off unlike normal Ram. So what is so great about having Ram as a hard drive? Well it’s all about the Speed. Just think about what it’ll be like to have a computer where you’ll never have to have loading times, what ever you want to load or look at will be there as soon as you finish the click. No loading no nothing! But as we all know Flash Ram and even normal ram doesn’t come cheap and from what I know a 2.1GB Solid State Drive costed $64,000 about 6 months ago and I would guess that it would be around $40 to $35 thousand today.

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