Replacing Hard Drive Guide
How to Choose the Best Hard Drive
for Your PC
This comprehensive guide will tell you all you need to know when it comes to replacing hard drives.
This may be a new build or maybe you just need to replace a hard drive due to failure or install new hard drive as a backup or for extra storage etc.
Your hard drive is the most important part of your PC. Why?
Simple, this is where all your programs and data is stored and for that reason alone you need to ensure that you spend time in selecting the best hard drive possible.
To do that use this guide to replacing hard drives which lists all the important points to consider when choosing the right disk drive for your PC.
Types of Hard Disk Drive
What are the main parameters we need to look at when selecting a hard drive?
Well, firstly we need to know the type of interface we require for our hard drive.
Then we move on to the size of storage space and finally on to speed and size of the cache or buffer memory.
When we've looked at all this and taken some notes on the spec we require we can go on to selecting a drive from the many hard drive manufacturers offerings out there.
There are many cheap hard drives with enormous storage capabilities available now and you will find that replacing hard drives is all very straighforward.
Hard Drive Disk Interface
PATA or SATA Disk Drives?
Serial ATA drives or SATA disk drives, are the disk drive of choice these days.
A few years ago the PATA or parallel ATA interface was the norm.
You can still get these if your motherboard is not equipped with the SATA interface and you require a new drive for your old motherboard setup for instance but for new builds or upgrades SATA disk drives are becoming the ones to go for.
Check your motherboard manual to see if it is SATA compatible.
Why have we gone over to the SATA disk drives?
Simple, they are much faster at transferring data - up to 300MB/s for the SATA II interface - also the interface cable is thinner with none of the old PATA master / slave drive allocations to worry about.
Hard Disk Drive Speed
Information or data is stored on platters or disks stacked one upon the other on a rotating spindle. A set of arms, one for each disk with a tiny arm mounted head sensor passes across the disk to read and write data to tiny magnetised regions on these disks which is where your data is stored.
The faster these disks spin the faster the data can be found and accessed.
Current speeds of rotation are anywhere from 5400rpm (revolutions per minute) to 7200rpm and finally up to 10,000rpm from Western Digital's Raptor X drive and the like.
Don't bother with the 5400rpm models when replacing hard drives, go for the 7200rpm type which won't cost you much more but will be much cheaper than the 10,000rpm models on offer.
Performance will also depend upon the time taken by the disk arm mounted read / write heads to reposition itself when accessing / seeking data from the disks.
So to sum up, look closely at the speed of rotation and access or seek times for comparison.
Most typical drives have seek times of around 9 - 11ms (millisecond).
Cache - Buffer Memory
This is the small buffer memory built in to the drive that holds frequently accessed data to save the drive having to continually re-read from the slow to access spinning disks.
2MB is the current minimum, 8MB / 16MB pretty standard and some models now boast 32MB cache size.
The more the better generally.
Hard Disk Drive Noise
You'll need to do some digging around the forums and reviews for this one as to the current state of play on who is offering the quietest hard disk drives if that is important to you.
Disk drives vary a lot in this regard and if the PC is going to take pride of place as your Media Center PC for instance you will quickly become annoyed if you have a particularly noisy hard disk drive installed, which some most definitely are!
Samsung disk drives have a well deserved very good reputation in this area.
Western Digital offer its Green Power range which dynamically switch between 5400rpm and 7200rpm which helps enormously.
Hard Disk Size - Capacity
You'll want to get a decent sized hard disk drive if you are planning on storing lots of video, photo's and sound files on your PC.
Typically an hour of raw footage direct from a digital camcorder can eat up 15GB of disk space and you'll be amazed at how rapidly the disk space gets eaten up on that shiny new drive of yours!
At the present time we would recommend anywhere from 500GB to 750GB as the sweet spot, maybe up to 1TB if you really need it and can afford the extra expense.
Solid State Hard Drive
The solid state hard drive is now becoming seen in more and more products such as mp3 players, USB drives, netbooks etc.
These drives, although by comparison with the mighty 1TB hard disk drives are quite small as regards storage space, have the benefit of very fast access times.
Their current high price is beginning to fall and as they develop these beauties storage capabilities further we will see them cropping up more and more because of their speed and reliability due to there being no moving mechanical parts.
Just like with flat screen TFTs and the old CRT monitors, these are certain to take over from mechanical hard disk drives and become the storage media of the future.
External Hard Disk Drives
These are useful if you want to provide a backup for your PC internal hard disk drive for instance.
They are basically the same hard disk drives that you would use within the case of your PC but housed in their own small case and with circuitry to allow the drive to connect to your PC by using the USB interface.
Some will derive their power supply from the USB interface and others, generally the larger types, will need a separate power adaptor to provide local power.
Hard Drive Manufacturers
You wont go far wrong if you stick with Samsung, Hitachi and Weatern Digital disk drives.
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