Benefits Of Partitioning A Hard Drive

There are several major advantages in partitioning a hard drive, and keeping your own files and documents on a separate partition.

In my computer repair business, when I build or buy a computer, the first thing I do is partition the hard drive.

What Is Partitioning A Hard Drive?

Partitioning a hard drive means creating more than one region of storage, so that each region can be managed separately.

Computers that you buy in the shops usually have just a single partition – so if you have a 500GB hard drive in your computer it would show as a single region of storage of about 465GB.

[Storage sizes are a bit of a marketing con, the usable storage space is always about 7% less than advertized. The same applies to USB flash drives, memory cards and external hard drives]

For historical reasons, that single partition will be mapped to drive letter C: and every file on the computer is stored in that region – all the Windows files, Program Files and (crucially) all of your important documents, pictures, music and bookmarks etc.

This arrangement is so common that many people refer to their hard drive as just ‘the C drive’.

But it doesn’t have to be that way, you can easily partition a hard drive into 2 or more regions of storage – the drive can then be treated almost as if it was 2 or more separate hard drives.

So it is possible to split that single 500GB hard drive into 2 (or more) regions e.g. a 120GB C: partition and a 345GB D: partition.

partitioning a hard drive

Not what we mean by partitioning a hard drive ;-)

What Are The Benefits Of Two Partitions?

With 2 partitions, you can keep using the existing C: partition to store Windows, Program Files and to install new programs on.

But you could move your own existing files (documents, pictures etc) to the new D: partition – and save all your future personal files onto the D partition.

So, the first region is reserved for Windows and programs (which need to operate from the C: partition) whereas the second region is used to store your own files.

The whole idea is to keep your personal files completely separate from Windows itself. There are many advantages in keeping your own files on a separate partition:

Easy Reinstallation Of Windows

If you ever need to reinstall Windows you can just format (delete) the C: partition then reinstall Windows in it – without affecting any of your own files saved in the second partition. Whereas, if you did this with only one partition, you would lose all your files as you would be formatting the whole drive…

Better Security

Viruses and malware typically target files on the main Windows C: partition – if your own files are also stored there they are more likely to be infected than if they are saved in a separate D: partition.

Note that this isn’t a certainty (some malware can indeed infect files stored in another partition) so a good backup solution is still essential.

Easy Image Backups

You can save a complete backup image (an exact clone/duplicate) of your whole Windows installation onto the second partition.

This image could be used to quickly restore Windows in the event of major problems (e.g. viruses or software errors) without losing anything – so all your settings, programs and Windows would be the same as at the time you created the backup image.

If you also copy that backup image onto an external USB hard drive, you could restore your entire Windows installation onto a new hard drive if your original drive died – without needing to reinstall Windows or any of your programs.

Note: You cannot save a backup image of Windows onto the same partition that Windows is installed on. So, if you only have a C: partition, you cannot create a backup image of Windows and store it on C:

Easy Data Backups

Having all your own files stored alone in one separate partition makes it easier to regularly back them up for safety – quicker than having to find and copy individual folders that are stored deep within Windows.

If all your files are saved in the D: partition you can simply create an image of that whole partition to backup all your data – or, if you use a backup program, set it to backup the whole D: partition, instead of having to select individual folders like Documents or Pictures.

Dual Boot With A Different Operating System

An advanced user might want to partition a hard drive to install a different operating system onto the second partition but that is outside the scope of the average home user.

What Are The Cons Of Partitioning?

We’ve looked at the Pros, but what about the Cons of partitioning a hard drive?

Well, splitting a hard drive into two partitions only allows you to treat it as if it was two separate drives. The total storage space is the same as before and you have not magically added a second physical hard drive into your computer.

So, if your hard drive dies completely, you will still lose everything stored in both the C: and D: partitions! But, if you took advantage of the easier backup options noted above, that shouldn’t be a problem as you can restore all your data onto a new drive.

The only other con is that the actual process of partitioning a drive has an element of risk – which is why I always recommend doing it when you first buy a new computer or install a new hard drive.

Windows 10 in particular makes the process easier but if you follow a good guide, and ensure you have made a full backup first, the benefits of partitioning even on an older computer can still be worthwhile. 

Is Partitioning A Hard Drive Important?

The eagle eyed reader will have noticed that almost all the advantages of partitioning relate to backups, disaster recovery and worst case scenarios like a virus or ransomware (encryption of files) attack.

Considering the speed of modern hard drives, there are no major performance benefits to partitioning a hard drive.

But the time you could most benefit from partitioning is often the time when disaster has struck and it is too late to do so – which is why we advise doing it before you need to…

To find out how, see our article on how to partition a hard drive.

5 Responses to: "Benefits Of Partitioning A Hard Drive"

  1. Roy says:

    Yes you can but it is more risky than doing it before you install Windows (when you have no data to lose if partitioning goes wrong)

    See the follow on article for details –

  2. Yogtav says:

    I have a question too, can I divide my hard drive in two partitions now? When everything is already set?

  3. Ihsan says:

    Thanks Roy for your good explanation…

  4. Ihsan says:

    In my computer, I created two partitions. I installed windows 7 in both partitions.
    In the first windows 7, I don’t keep any data. I will use it just web browsing, visiting any website without worrying about virus or spareware.
    In the second Windows 7, I keep all my important data. I visit only the website I trust.
    My question:
    if I get virus in the first windows 7, I can reinstall windows 7. Since there is no data in the first Windows, I don’t worry much. But I am not sure if the virus in the first Windows 7 affects the data in the second Windows 7.
    If I get virus or spareware in the first Windows 7, does the virus affect the second windows 7 and destroy my data in the second windows 7?

    • Roy says:

      Hi, that’s an interesting idea. I would probably have suggested using a virtual PC (and clone it) instead as you could start/close that without having to reboot and if it got viruses you could just delete it and start again with the cloned one.

      Anyway, the way you have it, viruses are ‘more likely’ to only infect the first W7 but there are a few dangers: 1. MBR viruses infect the MBR which is used by both W7 so the 2nd could become just as infected 2. Worms ‘may’ replicate across the whole PC, not just a single partition 3. If you ever copy files between the 2 W7s you could transfer a virus between them. The MBR virus risk is perhaps the greatest threat.

      So, you may get away with it (and it’s safer than having everything in 1 partition) but there are some viruses that could affect the second W7 too… You should make sure that the 1st W7 is up to date and has decent antivirus etc – or look into virtual PCs