How well does Windows 7 handle 512MB?

How well does Windows 7 handle 512MB?

Summary: I’ve been spending most of my time lately conducting in-depth research into how Windows 7 works, in preparation for my next book. In the process, I’m discovering stuff that simply doesn’t become apparent during casual testing. My biggest surprise so far? I inadvertently installed the 64-bit beta version of Windows 7 in a virtual machine with only 512MB of RAM. How well did it work? I was amazed, and you will be too.


Special Report: Windows 7

I’ve been spending most of my time lately conducting in-depth research into how Windows 7 works, in preparation for my next book. In the process, I’m discovering stuff that simply doesn’t become apparent to a casual tester. Case in point: Back in 2007, I looked at Windows Vista Home Basic and determined that it could run well on an older machine with limited resources, including 512MB of RAM. I never tried it with Vista Ultimate, nor would I have bothered. And since I don’t have that 2002-vintage test machine set up, I haven’t repeated those tests with Windows 7.

Earlier this week, I fired up a virtual machine running Windows XP SP3 so I could test upgrade scenarios with Windows 7. I couldn’t do a straight XP-to-Win7 upgrade, so I added a new virtual hard drive and installed Windows 7 in a dual-boot configuration. After making a few notes on how the setup process worked, I put the VM aside and went on to other work.

Windows 7 Ultimate x64 uses less memory than you might think

Windows 7 Ultimate x64 uses less memory than you might think

A few hours later, I went back to that new Windows 7 installation to look at a few details, and that’s when it struck me: This virtual machine was configured with a mere 512MB of RAM, and yet I hadn’t noticed any slowdowns during setup or in operation. Even more startling, I realized that I had inadvertently installed the 64-bit edition of Windows 7 Ultimate in this VM. But the most eye-opening moment came when I looked at Task Manager’s performance tab. I've pasted a screen grab of the memory gauge here.

The x64 edition of Windows 7 Ultimate running on just over 200MB of RAM? That was a pleasant surprise. I was also surprised to see that this clean install was using less than 9 GB of disk space in this VM. With my curiosity piqued, I configured a new VM using the same settings and did a clean install of Vista Ultimate, giving me a good baseline for comparing XP to its successors. Here are the stats for all three operating systems, with memory usage measured after all update operations had completed and the system had been idle for at least one hour:

XP Vista Win7
RAM (MB) 150 299 216
Disk (GB) 5.7 14.3 8.6
Or, in graphical terms, with the raw numbers normalized so that XP=100:

Windows 7 uses less RAM and disk space than Vista

Windows 7 uses less RAM and disk space than Vista

As you can see, on this low-resource configuration Windows 7 uses dramatically less RAM than Vista, and also has a smaller hard-disk footprint. A few configuration notes can help put these results in perspective:

  • For XP, the installation includes Service Pack 3, plus all available updates including Internet Explorer 7, Windows Media Player 11, and Windows Search 4. The only non-Windows application installed on this system is Firefox.
  • For Vista, the installation was of Ultimate Edition (x86) with Service Pack 1 and all available Critical and Recommended updates. No third-party software was installed.
  • For Windows 7 Beta, I used Ultimate x64 edition. As with the Vista installation, I accepted any Critical or Recommended updates and installed no third-party software.

The numbers and charts don’t really tell the full story, though. With identical configurations, Windows 7 was dramatically faster at starting up and shutting down than Vista, and some routine tasks that would grind the Vista machine to a halt completed without incident on the Windows 7 machine.

Just for comparison’s sake, I reconfigured each system to include 1024MB of RAM. With the extra RAM available, the delta between the Windows 7 and Vista VMs narrowed dramatically, although the 64-bit edition of Windows 7 still used less RAM than Vista. On the Vista system,. this upgrade made a noticeable difference, whereas the Windows 7 system performed about the same.

Clearly, the Windows 7 development team has taken a close look at performance and disk footprint when resources aren’t abundant. I suspect that when Vista was being designed, this was an afterthought, with the notion that cheap RAM and hard disks would make those machines obsolete. They didn’t account for netbooks or for the impact of solid state drives, which offer capacities that are much smaller than equivalent rotating media.

Why does Windows 7 use so much less disk space than Vista? A very small amount of the savings (much less than I expected) is in program code. The biggest savings is from the preallocated volume shadow storage space, which holds System Restore points and backs up files via the Previous Versions feature. On my Vista virtual machine, this feature was using more than 4.6 GB of disk space. Under Windows 7, the system reserved less than 400 MB.

This attention to performance when resources are less than expected on a modern desktop PC potentially has positive implications for netbooks and other cheap PCs. I might have to haul that old 2002-era Pentium 4 out of mothballs and see how it handles Windows 7.

Topics: Hardware, Microsoft, Operating Systems, Software, Windows

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  • How well does Windows 7 handle ARM processor?

    <font color=grey><em>"... potentially has <strong>positive implications for netbooks</strong>..."</em></font><br>

    The <a href=",1000000091,39527261,00.htm" target="_blank">next-generation netbooks</a> will be running an <a href="" target="_blank">ARM processor</a>.<br>
    Hence the <a href="" target="_blank">netbooks market is a race to the bottom</a>.<br>
    • We don't know...

      ..until Microsoft validate the architecture for W7. Which they will if the market's there.

      Cortex A9 multicores certainly have the grunt to support W7.
      Sleeper Service
      • It's not as simple as saying "we're adopting this new platform"

        There's a whole load of work that they'd have to do to rearchitect Windows for non-x86 hardware. The work that they do to get it run on Itaniums is difficult enough, and those are made by Intel - the market leader.

        It's very unlikely that you'll see anything until the next major release of Windows.
        • Unless there's money to be made...

          Sleeper Service
          • Of course

            But I don't see ARM adopting proper x86 any time soon, and x86 is (gradually) moving to x86-64. As of right now, the investment isn't worth it.
    • It doesn't but runs ....

      ... fine on the Atom.
      • Atom vs ARM - we will see

        "Atom may prove to be a little faster, writes Kenton Williston, but ARM chips are cheaper, more power efficient, smaller"

        Solid Water
        • The missing keyword is "for now"

          "Atom may prove to be a little faster, writes Kenton Williston, but ARM chips are cheaper, more power efficient, smaller"

          This is *Intel* we're talking about. They've already reached 32nm, they're already versed in power efficient design, and they have a serious desire to make money. :)

          Oh, and lets not forget the magic that is "economies of scale".

          You do the math. At best ARM will hold its own--at worst they'll become another AMD.

          Either way, MS will have a platform they already run on. And since Windows went from 0% to 80% in the netbook market (using a 9 year old OS yet!), I wouldn't bet against them, especially when Win7 comes out.
    • Windows CE supports ARM

      Microsoft has had Windows CE running on ARM processors since the 20th Century. Of course back, then the Windows CE Handheld PCs were still pretty expensive.
  • RE: How well does Windows 7 handle 512MB?

    This is good news! I just bought an MSI Wind and cringe having to use XP, but don't want to put Vista on a machine that has a 1.6ghz Atom processor. If Win7 can run fine on it then that would be awesome!

    Any chance you have a netbook to test this stuff on? ;)
    • I'll tell you now...

      I've had my laptop for 5 years and it runs just
      perfectly with Windows 7. Full-featured and
      everything! Aero effects and messenger, web
      browsing (with Chrome obviously...) and no
      hangups! This machine has 1GB of RAM as I
      couldn't bear the 256MB that it came with so I
      upgraded probably just under 2 years ago. The
      processor is only an AMD Radeon Mobile 1.8GHz
      processor and yet it runs perfectly. I'm 99%
      positive that it will work on your machine.
      • Can not find AMD Radeon Mobile 1.8 GHz CPU... :-)

        What kind of a beast is this one?

        I know that there is a graphics chip: ATI Mobility Radeon? X1400 which was/is one of the speed demons in the notebook world. For details see:

        Not to mention that 1.8 GHz AMD will be definitely faster than 1.6 GHz Atom.
        Solid Water
        • Yeah, sorry.

          I was thinking of the graphics card. Okay, now,
          when I go to dxdiag, it says my processor is
          the Mobile AMD Sempron(tm)3000+ at 1.8 GHz.

          And yeah, my graphics card is one in the Radeon
          XPress series.

          Sorry that I got those confused!

          And yeah, I was really only trying to emphasize
          how well Windows 7 runs on my 5 year old
          machine. There's a lot of stuff that I would
          never have dreamt of putting on here and yet
          Windows 7 somehow just glides right through.
    • Note, Win7 still takes more resource than XP

      I don't know how serious you were about "cringe having to use XP", but just a reality-based note -- nothing said in the article indicates you'll be OK with Win7 if you're NOT ok w/ XP. Just that compared to Vista, you're better off.

      Maybe it was a typo, and you meant you cringe having to use Vista on your Wind -- or you cringe at using XP for other reasons than performance.

      If only I could talk to you about Linux ... but i don't want to wake the sleeping lurkers who would deride me (not in the mood today ;-).
      • And this is a surprise to you???

        Win7 is doing A TON more work behind the scenes than XP. That work takes resources - CPU, memory, disk and IO. For example, file indexing, extra security measures, firewall, IPv6 network stack, etc.

        Having said that, in Win7, most of that work is being done in the background on low-priority threads.

        The net result is that although Win7 uses more RAM than XP, much of that RAM is used to cache frequently used files and so makes up for the extra work that Win7 performs, resulting in Win7 feeling comparable, and in some cases, faster than XP on the same tin.

        Net-net, Win7 takes a little more resources, but delivers a VERY responsive experience.
      • No

        I meant what I said, it's hard to go back to XP after using Vista. Why would I cringe at using Vista? It's awesome, XP is antiquated (much like Linux or OS X).
    • XP on Atom

      Xp runs way better than you think on an Atom. I have the Aspire One I use when on the road. I sometimes need to do customer support on a SQL Server app we sell. Performance is perfectly acceptable.

      • I agree

        XP works nicely on the Atom, but the OS itself is lacking so many good Vista features. Since Win7 is going to run more smoothly than Vista anyway, I'd rather do that than Vista.
  • This is not a breakthrough

    In the early 90's I used to run SunOS on a 16MB box. A reliable
    multiuser operating system with multitasking, networking, and a
    graphical interface. In terms of capability operating systems have
    not advanced much, and yet needs 32 times the RAM. This is not
    a breakthrough, people. Wake me when the next version of
    Windows can run in 16mb.
    • Confirmed... with OS/2

      I was running it in i386/? MHz/16 MiB RAM in 1994.

      Still have good memories about its reliability and performance.

      IBM might think to come up with its own operating system for netbooks. :-)
      Solid Water