What to look for in a hard drive and why
The Bottom Line What makes a good hard drive? Is speed as important as space? These are questions to ask yourself when shopping for a new drive.
When you go shopping for a hard drive there are several things to consider. Each of these things can greatly effect the speed and performance of the drive. The name of the manufacturer is not as important now as it used to be because the new IDE or EIDE hard drives have become so reliable now that the manufacturers name really doesn’t make a difference except in the price.
The first thing I look at when shopping for a hard drive is the RPM of the drive. RPM stands for the same thing RPM stood for on old vinyl records, Revolutions per minute. Most IDE hard drives today are either 5400 or 7200 RPM. The 5400 RPM drives are not bad but they do not start applications as fast as 7200 RPM drives and do not boot as fast either. So I look for a 7200 RPM drive.
The next thing I look for is the Seek time. The seek time is measured in milliseconds. Average seek times are around 9ms. There are drives with 8.5ms seek times. I haven’t seen any faster than that yet in IDE format. The faster the seek time, the faster the hard drive can access and retrieve data. A drive with 8.5ms seek time and 7200 RPM is a good drive for fast access of data.
Another thing to consider is the type of controller you have on your computer. ATA100 controllers are becoming more popular and are being used in most new computers these days. Older computers use UDMA33 or DMA. You can use an ATA100 hard drive with an older controller but you will not get the faster transfer rate. The difference in the two is ATA66 or UDMA66 transfers data at 66.6Mbps and UDMA33 transfers data at 33.3Mbps. The special ATA66 controller uses an 80 wire EIDE cable instead of the regular 40 wire cable giving it twice the bandwidth for data transfer. Even though it has double the wires, it still has a 40 pin connector so you can use either drive with it. But if you have an ATA66 controller and use a drive that only supports UDMA33 you will only get the 33.3Mbps transfer rate.
First, I apologize for not updating this sooner but I have been busy with other projects. In late summer this year a new controller sprung into the IDE world called ATA100 or UDMA100. These controllers have been called a variety of names by their respective manufacturers including “ATA future device”. These controllers open the data transfer bandwidth to an astounding 100mb per second at maximum burst rate. New hard drives are being made by virtually all manufacturers to take advantage of this new technology and still be compatible with the older 33.3mbps and 66.6mbps data rate drives. If you have one of these newer controllers I suggest making sure the drive you get is rated 100mbps to get the best data transfer rate out of your new hard drive.
The size of the drive you want depends on what you plan to do with your computer. If you’re just browsing the web and sending email, maybe a little word processing, you probably don’t need more than 40 gigabytes. If you collect MP3’s or design graphics, you may want a larger drive like 80 or 120 gigabytes. Personally I have a 300 gigabyte drive made into three 100 gigabyte partitions to make file sorting easy.
If you really want a fast drive you will need to consider getting a bootable Ultra Wide SCSI controller and a SCSI3 hard drive. These drives have a data transfer rate of 80Mbps and the latest ones up to 120Mbps. You can also get them with 10,000 RPM. I use SCSI for my hard drive and it is by far the fastest and most reliable yet.
Another important feature commonly overlooked is the buffer. The buffer on the hard drive is a simple memory chip that helps the hard drive transfer data to and from the actual platters in the drive. A good size for a buffer is 8MB or more. Some older drives only had 256k buffers and the difference is impressive with a 8MB buffer. Remember to check how big the buffer is before you buy.
I hope this helps you in deciding what to look for when shopping for a hard drive.
If you need help deciding which hard drive is right for you contact firstname.lastname@example.org