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My operating system is Windows 7 Vista Home Edition, and I have a 464 GB disk drive.

So far I have used 198 GB out of it.

As I understand it - 464 GB = 464 x 1,024 MB = 475,136 MB.

196 GB = 196 x 1,024 MB = 200,704 MB.

When should I start worrying about disk space? According to Disk Management I have 196.28 GB (about 42% free). I already have an external USB drive.

However, since my PC has essential apps on I use for work/commercial purposes (self-employed individual), work documents, and Microsoft Office, is it worth installing another disk drive? It's a home PC, by the way, not a corporate one, but treated as a business app.

As far as I'm aware virtual disks are just files, so that's ruled out for now.

Do I need to worry about this or not just yet? - I only really deal with software, rather than hardware much in the typical working day so I hadn't considered this until now...

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what is your goal? just worried about having enough free space, or more worried about backup/security of your data? – Xantec Apr 14 '11 at 19:48
Bit of both, really... – Aquila5 Apr 14 '11 at 19:50
Do you have a backup strategy? If your hard drive fails can you recover, or are all your important data and programs gone forever? I would be concerned when you get down to 5gb free space. – Moab Apr 14 '11 at 19:50
Well it depends on what you do with your computer, 196GB is plenty for me but for someone who has lots of media or runs a DataBase they may think of 196GB as "running low". My suggestion: get an extra disk and use it for back ups if you eventually need the space you will have it. – Not Kyle stop stalking me Apr 14 '11 at 19:54
Thanks. Yes, I do have the USB drive as my only strategy for now... it was just 198 out of 464GB looked like it was small. Oh well, I learn something new. – Aquila5 Apr 14 '11 at 19:57

I would concern myself about disk space when you have ~25% free space remaining. Free space tends to go in waves. You may be fine for a month not adding any new data, but then splurge one month and eat up a large chunk of it.

When the free disk space falls below 15% slowdowns can start to occur. This is caused by two things:

  1. The swap space (ala computer's scratch pad) is split up on different parts of the hard drive.
  2. The files being accessed are more likely to be fragmented and parts of the file will be on different parts of the hard drive.

I usually have two hard drives in a desktop computer.

  1. The first hard drive contains the OS and applications.
  2. The second drive contains all the data files (movies, music, etc)

This can give you a minor speed bump as well since the each hard drive is doing less than a single hard drive.

For more secure backups you should have the data in three places.

  1. The original data on your hard drive.
  2. A different internal physical disk or an external USB hard drive.
  3. An offsite backup (ala Carbonite, Mozy, etc)

This protects your data from theft, fire, earthquake, etc...

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regarding backup strategy; off-sites are good and some would say critical for any "if I lose this I'm dead" data. however, while not trying to create an atmosphere of fear, keep in mind that there is no such thing as a 100% fail safe system – Xantec Apr 14 '11 at 20:35
@Xantec true, it's not fail safe. But if something takes out both local backups and an online backup you are probably going to have more important issues to deal with :-) – Patrick Apr 14 '11 at 20:42
An off site backup can also be something like an external hard disk which you keep in your desk drawer at work. – Michael Kjörling Feb 6 '15 at 13:38

You don't have to worry until your free space gets to less than, say, 10% of your total. You can but don't have to add a second hard drive. And, as always, make sure what you do have is backed up, which would be a good use for your current USB drive.

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The USB drive's got older stuff on it, 425GB out of 1TB used... but that's only for extremely sensitive material. (not that I can go into detail here, obviously). As for adding a virtual drive, what's your opinions on such things? – Aquila5 Apr 14 '11 at 19:56
Not sure exactly what you mean by virtual disks — do you mean partitioning the drive differently (C:, D:, etc) or like using disk images? There can definitely be benefits in having different partitions, but it adds likely unneeded complexity. As for disk images, unless you're planning on encrypting them, I can't see much use. – emgee Apr 14 '11 at 20:02

Like emgee says, you probably don't have to worry about it right now.

If you're just dealing with documents and such for the most part, you're not going to fill up 250GB more data very quickly.

And you already have an external drive, which I assume you use to backup critical files, so you don't need more disks just for backup and security.

However, there are a couple things that need to be addressed:

First, megabytes and Gigabytes are measured not in strict mathematical sense of Giga equalling 1000 Mega's, they are really based on a factor of 1024, which has to do with how computers count more than anything else. The numbers that harddirve makers use will vary depending on how they want the drive to look, some will be based on a 1000 factor, and others on 1024 factor, and you'll see both on the same package sometimes with no label to show you which is which. Because of this it really isn't important, except in an abstract sense, to try and match of 196GB with 196,000MB. It's useful to get a ballpark figure, but not if you're looking for accuracy.

Second, virtual disks have nothing to do with increasing the amount of storage on your computer. Think of a .zip file: it is a file that contains other files. A virtual disk is just that except with a different purpose. A virtual disk is a file that contains other files, specifically for the purpose of pretending to be a hard drive for a virtual computer, which is a computer that only exists in software running on a computer. Virtual disks and Virtual computers are used for testing, application development, "sandboxing", and in some cases saving power and resources by allowing a single physical computer to act like several different computers.

Finally, being more familiar with software than hardware is perfectly OK. Most of the world gets by just fine being much more familiar with software then they are with hardware. Computer makers know this and hard drives and storage options are becoming increasingly easy to apply and use by software people, such as yourself.

Even if you start working with and making significantly more data than you are now and find you are running out of space, you can get huge external hard drives nowadays for relatively low prices. And just like your current external hard drive, you just plug it into your computer and begin enjoying tons more space easy as that.

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