Does Vista really need 15GB of disk space?

Does Vista really need 15GB of disk space?

Summary: When you run the new Windows Vista Upgrade Advisor, you'll find that Vista won't install unless you have 15GB of disk space free. Is this the most bloated OS upgrade ever? Nope. The actual installation uses much less space. Here's why.

TOPICS: Windows

Last week, Microsoft announced the immediate availability of the Windows Vista Upgrade Advisor Beta, which it bills as “a small beta application that you can run on your current Windows XP-based computer to find out if it's ready for an upgrade to Windows Vista.” (This image gallery shows the Upgrade Advisor in action.)

I’ve run the Upgrade Advisor on several computers in my office. The one surprising result is the seemingly excessive disk space requirement for Windows Vista. On a relatively new Acer Tablet PC that otherwise meets all the Vista specs, I received this warning:


That’s an eye-popping requirement at first glance – 15GB of free disk space? Is Vista going to be a big, bloated OS upgrade after all?

In short, no.

That 15GB requirement is a reflection of how the new staged setup program for Windows Vista works. Vista’s predecessors, including Windows XP, perform a file-by-file setup. The staged installation copies a disk image containing a full, ready-to-run installation of Windows Vista, installs drivers for your hardware, migrates your data, and finally cleans up after itself.

I’ve installed Windows Vista Ultimate Edition on a few PCs in my office. The core installation takes up a little over 6GB of disk space, plus additional space for a paging file and hibernation file – the exact size of these two files varies depending on how much RAM is installed on your computer.

So, yes, you will need 15GB of free disk space. But the good news is, when you’re done you’ll still have plenty of room for data.

Topic: Windows

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  • Hopefully this will mean

    installs are MUCH faster. If you do a comparison test of an XP install versus any other major OS (not including a stage 1 or 2 Gentoo install) and it would come in dead last. And Windows installs less software than those other distros.
    Michael Kelly
    • Copy the entire CD

      BEFORE the install happens. Just how "fast" do you think THAT will be?
      Roger Ramjet
      • XP on CD, Vista on DVD

        Vista Beta 2 comes on an ISO file intended to be burned to DVD. It's over 3GB all on its own!
        Ed Bott
        • So, copy an entire DVD

          BEFORE starting the install. And then it STILL installs via CABs (now on the hard drive)? Doesn't sound very efficient.
          Roger Ramjet
          • You're still not getting it.

            You're describing the XP install process. In Vista, the contents of a compressed image file (in WIM format, not CABs) get copied to the hard disk during setup. The image file gets expanded into a working copy of the OS. Hardware-specific drivers are then installed.

            This is a process very similar to what corporations have been using to configure PCs using Ghost and Sysprep for a few years now. It works well.
            Ed Bott
      • Faster thatnNOT copying the CD, and running off the CD Drive

  • Corporate images

    Plus, remember that this tool is for the default, factory Windows installation. I'd imagine that in corporate scenarios, administators would create their own custom images that have stuff removed. Though, this probably would have a rather small impact on the actual disk space used.
  • 6 GIGABYTES?!?!?!?!

    You think that's not eye-popping and belt-busting?

    For a "core" install.......

    XP and full Office 2003 is 1 and 1/2 gig. I think that's gigantic. 6 gigabytes. Geeez.

    Bloatware lives!
    • And?

      The space requirement for Win9x/ME was a couple hundred megs, and people like you complained about it. WinXP required 2 Gigs, and people like you complained about it. Vista will require 6 gigs, and sure enough, people like you are complaining about it. So what's new?

      Right now, a 200GB SATA hard drive is around $75. An 80GB drive is under $50. By the time Vista ships, the prices will have dropped even further. You'll be able to fit around 30 Vista installations on a 200GB drive.
      • So

        So instead of relying on MS to write tight, clean code, we're going rely on ever-increasing hardware requirements to pick up the slack.

        So the Redmond crew could produce more flash, NT went (if I recall correctly) from 1/2 million lines of code in the 2000 interation to 3 and 1/2 million for XP. Sure XP had a few real technical improvements, but not 7 times better.

        So what's it going to be for Vista? 20 million? For what? What's in it? I don't know, but I am not anxious to roll out a piece of software that can't help but be inherently buggy. XP has been quite bad enough, thank you.
        • You are engaging in logical fallacy and citing incorrect facts

          First of all, it is not correct to assume that Vista requiring so much more space automatically means that the code is not written tightly. You are completely discounting the addition of more features, more drivers, and more media, etc.

          Second of all, your numbers about lines of code for 2000 and XP are [b]way off[/b]. For the real numbers, check this [url=]link[/url] out.

          From that page:
          [b]Win2k = 29 million lines of code
          WinXP = 40 million lines of code[/b]

          Third of all, I must quote you...

          [i]So what's it going to be for Vista? 20 million? For what? What's in it? [b]I don't know[/b]...[/i]

          Emphasis added by me. ;)
        • Just curious, how does OSX compare to Mac OS7?

          Or the newest Linux kernels to the original? The fact is, new OS's do a lot more than the older OS's, have a lot more things they need to work with, and so they are larger.
          Not saying MS couldn't make it cleaner, just that the size is going to grow regardless.
    • So what?

      Can you find me a comparable (up-to-date, full-featured, and mainstream) OS + Office app that uses less than 1.5gb? The average Linux installation requires at least that much. Roughly one to two gigs for a home PC is the norm at the moment.

      I agree with you that 6gb is alot by comparison, but you can't add more features without taking up more space. Besides that, hard drives are getting cheaper by the day. I just bought two 160gb SATA drives for $30 each after rebate from CompUSA a few months ago -- only about $70 before rebate. But if you absolutely must have all possible space: don't buy Vista. Switch to Windows NT Workstation and knock yourself out.
    • Nice try, but where'd you get your copy of XP?

      I have a clean Windows XP Professional test system here with only Office 2007 with OneNote, Firefox, and Adobe Acrobat Standard on it. No other software.

      The C: drive is using 8GB.

      According to Control Panel, Office and OneNote use up a little over 1GB and Acrobat uses just under 500MB. Firefox is less than 15MB. Subtract all that software and what do you have? 6.5GB.
      Ed Bott
      • You forgot to...

        ...subtract the pagefile and hibernation file.

        At work, our standard XPSP2 images are around 3.5GB IIRC. 8GB sounds about right if you added the pagefile, and hibernation file and the apps you described.
        • Nowhere near that big on this system

          This is a reasonably clean VM, with no hibernation file and only a 768MB paging file. Round it up to a gig and this install is still over 4GB.

          Anyway, the point is that goldfly needs to take a closer look at those XP installs.
          Ed Bott
        • Oh, one more thing...

          This is Vista Ultimate Edition, with full Media Center features. An install of Home Basic or Home Premium would presumably be a lot smaller.
          Ed Bott
          • One LESS thing

            After scratching my head for a while, I presume you're changing contexts here, and no longer describing your XP VM install... I'm not sure what you're describing. Vista SP1? I would expect them to use a single installer for all versions, as they do for Vista itself.

            Anyway, there's something very wrong with your numbers. The XP VM I happpen to have running now isn't minimal -- but only uses 2.14 GB INCLUDING PAGING. It's nearly up-to-date with patches, so it has 385 MB of uninstall data for undoable XP updates that I could delete. Subtract the paging file, additional software I can easily locate, etc. and I get right around 1GB for XP, including the uninstall data.

            But a lot of stuff gets dumped into the Windows folder -- including by Office. It's not uncommon to see large XP Windows folders, but it's incorrect to blame that on XP.

            I'm not griping about the size of Vista though. On my laptop, in addition to my main Vista Ultimate install, I have a couple of Vista Ultimate VMs and several XP VMs. And Office, and the Beta of the new Visual Studio (which is a 5GB DOWNLOAD), and a host of other development software, not to mention multiple development copies of my company's software.

            Yes, I'll be upgrading my hard drive soon, but it won't be Vista driving that -- not even close, not even multiplied by N virtual machines.

            Remember, too, that functionality in the OS is functionality that you don't have to add on, often two multiple applications. So on Vista, I don't have to add on Google Desktop. (I do anyway, but it's less of a loss if I didn't). Growth in OS size is not entirely a bad thing, at least compared to some of the alternatives.
      • Dude, WinXP Pro, Office 2003, Firefox under 3 GB

    • The average HD sold these days..

      for desktop systems is in excess of 150GB. The average video game takes up between 1 and 4 GB. Somehow even installing 15 GB of operating system doesn't seem so bad then.....never mind 6.