Original URL: http://www.theregister.co.uk/2006/08/02/review_bootcamp_parallels_desktop/

Windows on Mac: BootCamp vs Parallels Desktop

How to run the 'other' operating system...

By Tony Smith

Posted in Hardware, 2nd August 2006 15:04 GMT

Review Almost as soon as Intel-based Macs were available to buy, clever coders were trying to figure out how to run Windows XP on them. Mac OS X not good enough for you, guys? Well, in some cases no, it's not. Mac OS X may be the better product - discuss... - but Windows has access to far more software applications and hardware toys that the Apple operating system does. From gamers to software developers to business users, there are solid reasons why a Mac user might want to run the 'other' operating system.

And not just Windows XP. Running Linux has always been an option, thanks to the sterling work of LinuxPPC coders stretching back more than ten years, but now Mac users have the chance to sample some of the more modern alternatives running on x86 CPUs, like Ubuntu. Then there are the leftfield options like OS/2 and, a personal favourite, the BeOS, now defunct as a commercial product but available as the Intel-only Zeta.

windows on mac

But there's a basic question that needs to be answered before we can all enjoy tinkering with alternative operating systems on or Macs: how is this duality to be achieved? Both Windows and Mac OS X access hardware resources in different ways, so there's no way literally to turn a Mac into a PC. You can't format the hard drive and install Windows on top of it. There have been hacks to make this possible and to allow an Intel-based Mac to play host two both Mac OS X and Windows, and they've been followed up by more commercial tools. This month, Apple updated its offering, BootCamp, while a small company called Parallels released the final version of its own Windows-on-Mac tool...

Parallels Desktop for Mac 1.0

Parallels Desktop (PD) is very definitely for folk who want to use another operating system on a casual basis. It's benefit of fast access to the guest OS is balanced by reduced performance and limited hardware support. It's not a tool to use if you're a gamer, say, but rather for dipping into that legacy accounting package you're still using after all these years.

That's not to demean PD - getting multiple operating system to operate alongside each other simultaneously remains an impressive technological feat, and Parallels' software is both ingenious and amazingly cheap. PD manages the trick of mediating between guest operating systems, Mac OS X and the hardware they're all running on. The host OS believes its operating alone; the guests each assume they're the only show in town; PD is the magician behind the curtain making it all work seamlessly.

Installation is remarkably straightforward - particularly in comparison with BootCamp. PD itself is installed in the usual Mac OS X manner. Running it invites you to set up a Virtual Machine - the ersatz PC on which any variety of Windows, of Linux or of a number of other operating systems will be fooled into thinking they own. There's no need to re-partition your hard drive - PD creates .hdd files and ties them into each VM as if they were physical, separate hard disks.

windows on mac - parallels desktop installation

PD places the .hdd files in your own Library folder. You can move them, but you'll need to let PD know explicitly - it can't resolve aliases, for example. But even so, it's easy to move the .hdd file off onto an external drive if you don't have enough space on your main hard drive. PD ships with an integrated disk compression tool that runs in Windows to defragment the virtual hard drive, clean out unneeded temporary files and so on. Parallels also supplies a separate utility for creating and modifying hard drive and optical disc images.

With a VM created - manually or using a Wizard - it's a matter of starting up the VM, inserting the guest OS' own installation disc and loading the operating system into the virtual hard drive. Windows XP installed smoothly, as did its Service Pack 2 update. Parallels has provided a set of drivers to tie key Mac hardware components into the guest OS, and these are installed once you've got the guest OS up and running. With XP, these Parallel Tools add graphics, mouse and trackpad, network, shared folder support to allow data-sharing between operating systems, and other drivers.

windows on mac - parallels desktop options

The upshot is that you can get up and running quickly and smoothly. The downside is you're tied to Parallels' virtual hardware design. There's no driver for the MacBook Pro's integrated webcam, for example, or for its Bluetooth adaptor. But then my MacBook Pro's trackpad worked perfectly, right down to tapping with two fingers to emulate a right-button mouse click. The XP VM uses the host machine's internet connection, but whether Mac OS X talks to the outside world across a LAN or a wireless link, XP always assumes it's on a fixed network. Your optical drive appears as a CD-ROM/DVD-ROM - there's no burn capability.

windows on mac - parallels desktop operation
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Some of these hardware features can be tweaked - you can set the network bridge to connect specifically to the host Mac's Ethernet or AirPort adaptors, for example. Most users, I suspect, will stick with the default settings.

With XP running, I tried installing ATI's Radeon Mobility X1600 drivers, but when the installer inspected the hardware configuration as presented by the VM, it decided my machine was not one supported by ATI. As it stands, Parallels' own video driver will not do 3D acceleration. The 3DMark 06 benchmark would not run, and neither would the 3D components of PCMark 05 so I couldn't get a full PCMark rating. For what it's worth, the CPU test yielded a score of 2,891 while the HDD benchmark results was 4,943 points.

You'd want to install the latest ATI drivers to maximise your machine's graphics performance under XP. But there are other limits. Even though XP correctly identifies the host processor, PD limits the guest OS to one of the Core Duo's two cores. In practice, XP and OS X both throttle back apps that are running but sitting in the background, so this is unlikely to hit mainstream applications hard, but it will hinder processor-hungry tools like Photoshop.

You can assign as much memory to the VM as you have physical memory on board, but PD suggests you leave enough for the host OS to run smoothly, and provides a recommendation. My MacBook Pro has 1.5GB, and I assigned the recommended maximum of 1.1GB to the VM, and there was a marked impact on Mac OS X performance. Even running the VM at 768MB, allocated all but 16MB of the physical RAM to other tasks, and that's with just Mac OS X, a handful of dashboard widgets, Activity Monitor and text editor, Text Wrangler, running alongside PD. Switch off PD, and the free memory shot up to 970MB.

Depending on what you plan to run under PD, then a memory upgrade may be in order, which adds to the product's overall cost, of course.

windows on mac - parallels desktop operation
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There are other issues. Parallels' routines for changing to full-screen mode needs some work. Out of the box, it messes around with the two OS' resolutions too much. Fortunately, you can tell PD not to change the Mac OS X screen resolution, and you can turn off the transition effects, but I repeatedly saw graphical oddities in XP - missing UI elements, wrong resolution messages and so on. There's no way, it seems, to flip seamlessly from full-screen Windows to full-screen Mac OS X as if you were sharing a monitor between two machines.

Even in full-screen mode, the VM essentially runs in a Window. That's handy in some ways - Apple's volume and brightness controls continue to work as before - but irritating on others, primarily the way Exposé's hot corners are retained. Push your mouse too far and suddenly Windows disappears entirely.

windows on mac - parallels desktop options

These are minor irritations and easily avoided. And they're a small price to pay for the flexibility of not having to reboot your Mac to change operating systems, or to be able to run multiple operating systems without having to re-partition your hard drive, with the risks that entails. Equally important is PD's ability to with other operating systems than Windows XP - which is all Apple's BootCamp officially supports. That makes PD the only choice for legacy operating systems, such as Windows 3.11. It also provides an easy way to trial Linux.

Parallels Desktop for Mac costs $80, but you may need to add some extra memory too and the cost of a copy of Windows. Fortunately, Parallels lets you try the software out for 15 days, which should give you a sense of the performance limitations and/or expanded memory requirements your chosen guest operating system(s) will require if you choose to stick with PD.


Apple's BootCamp software doesn't work the same way as Parallels Desktop. While Parallels lets you flip in and out of the guest operating system at will, BootCamp forces you to start up in Windows XP or Mac OS X. Want to switch back? Then restart again and select your original OS.

The upside is that Windows gets full access to the system's resources, so there's no performance hit, and you're free to install vendor-provided drivers for the GPU and so on. Forcing a restart means each OS runs more cleanly - there's no intermediate code juggling access to resources. All your memory is devoted to each OS, so there's no need to worry about making sure each gets sufficient to do what it needs to do.

The price you pay for that is the need to tweak the partitioning of your hard drive and the risk of data loss that, however small, this process invites. And since BootCamp won't be finalised until Mac OS X 10.5 ships, you'll be running pre-release test software, so you're open to whatever bugs Apple's developers have yet to fix. If something does go wrong, you're on your own. As I mentioned before, BootCamp also officially limits you to Windows XP.

windows on mac - bootcamp installation

But nothing ventured, nothing gained, so into the melee I dived. Tweaking hard drives is always a scary process, so make sure you back up all your data first. Reports from folk who've tried it already suggest that it's a good idea to verify your hard drive and repair file-access permissions before running BootCamp. Both tasks can be achieved by running Mac OS X's own Disk Utility, ideally by booting from a Mac OS X installer CD or DVD first. I also left the machine running unused for half an hour or so to allow the OS' auto-defragmentation code to do its stuff.

You'll also need to make sure you're running Mac OS X 10.4.6 at least, and that you have the latest firmware installed. Software Update may not show it, but you can download the updater from Apple's support website.

Hats off to Apple, BootCamp is a nicely wrought utility. It's delivered through BootCamp Assistant (BCA), which does its level best to make the Windows XP installation process as smooth as possible. The download incorporates almost all of the drivers you'll need for Apple's hardware, and BCA makes an installer disc for you. Once that's done, the utility dynamically repartitions your hard drive without forcing your Mac OS X partition to be reformatted, saving you (hopefully) from having to back up your data and applications, then reinstalling them again after you're reinstalled Mac OS X. As ever, Apple's UI is simple and easy to grasp: just drag the boundary between the two partitions to set it. As you go, the window always tells you how much free space you have.

windows on mac - bootcamp installation

If you tire of Windows, BCA will also remove the Windows partition, destroying all your Windows apps and data. Back to the install, once BCA has repartitioned your hard drive, it asks you to insert your Windows XP disc - Home Edition or Professional, but they must both be Service Pack 2 - and then restarts our machine from the CD.

The XP installation process ran smoothly. It correctly identified the 8GB partition I had BootCamp Assistant create as its C: drive, which I formatted as an NTFS volume as XP installer suggested. The first post-installation reboot left me with a blank screen after the initial XP start-up screen, so I forced a shutdown and restarted manually. This time I got the correct Set-up screen and was able to complete the XP installation. Incidentally, the video glitch seems an issue Apple needs to address. Even with the ATI drivers installed courtesy of the CD BootCamp makes, there's a distinct pause between the initial XP screen and the Welcome image.

Installing the BootCamp drivers CD went well, too. The process has a habit of triggering Windows' hardware detection system - or this happens anyway - but I ignored it completely, only clicking on windows warning about unqualified drivers, as per the BootCamp instruction manual. As Apple admits, there's no support for the integrated iSight camera or for some of the more advanced features of the trackpad, though it works.

windows on mac - bootcamp installation

Running XP afterward was a joy. With access to all the MacBook Pro's memory and both processor cores, performance was nippy and generated a PCMark 05 rating of 3,369. Unlike Parallels Desktop, this XP install could run the full range of PCMark tests, including the 3D graphics benchmarks. For comparison, BootCamp's CPU score was 4,061 - 71.2 per cent faster than PD's scored 2,891.

3DMark 06 at 1,280 x 768 yielded 1,112, which is nothing to write home about even for a notebook. Then again, Apple's clocked the GPU to around 310MHz - roughly two-thirds of what the Radeon Mobility X1600 can go to.

The only problem I encountered was a Blue Screen of Death immediately after installing Skype 2.5, but I've since run a range of apps without any such hiccups. The first time I rebooted back into Mac OS X, I experienced an odd glitch: after an hour or so's use, a couple of files newly placed on the desktop disappeared. But they reappeared after a reboot and I've not had a re-occurrence of the issue since. A Disk Utility check revealed no problems with my Mac OS X partition. Occasionally after a Windows session, Mac OS X loses track of British Summer Time and defaults to GMT. This is irritating, but the sort of thing you expect with beta software.


It's tempting to present this review as a head-to-head, but while BootCamp and Parallels Desktop do the same thing - allow you to run Windows XP in addition to Mac OS X - they're sufficiently different to appeal to different types of user. Which you pick should depend on what kind of software you want to run.

apple boot camp xp-on-mac utility

PD first. This is ideal for anyone who wants to run one or two mainstream Windows apps, either because you can't get Mac OS X versions or because they're tools your business has been using for years and you've simply got too much data tied up in them to jump ship. PD has a minimal impact on your system, making it as easy to dispose of as any other Mac application. Mac OS X's inherent stability means Windows hiccups aren't going to affect you any more than a Safari crash might.

Yes, there are performance limitations, but I found them broadly acceptable. I hope Parallels works on fixing the hardware support for iSight, Bluetooth and a broader array of USB devices. A better graphics driver, to allow 3D acceleration would be nice, but isn't essential.

Chances are if you need 3D acceleration, you're going to want BootCamp rather than PD anyway. BootCamp delivers the full hardware to Windows - all the memory, primarily - and with a decent set of drivers - everything but the iSight camera, it seems. This is the solution for gamers, graphics professionals and anyone who expects Windows XP to run as if it were running on a second machine. Unlike PD, BootCamp is for folk who want to run XP or OS X at any given time, not XP and OS X. That largely means anyone who wants to dedicate as many processor cycles as possible to a specific task, or you expect to spend a significant time running just one OS.

The downside, for now, is that BootCamp isn't ready for mission-critical apps, so PD may make for a temporary solution until BootCamp 1.0 ships with Mac OS X 10.5. PD is also beholden to Mac OS X's power management system, so it's fine - performance and hard disk thrashing notwithstanding - to run on an untethered notebook. BootCamp's drivers are less sophisticated, and notebook users should expect shorter runtime on battery than they might get under Mac OS X - the graphics chip will probably run faster, for example.

BootCamp is free, of course, but PD's $80 price tag is extremely good value for such an easy to use, Mac OS X-friendly and - crucially - safe tool. Frankly, if after reading the above, you reckon PD is the best solution, you're better off buying the software than try to use BootCamp to save money.

PD has the most potential, however. BootCamp offers the best performance, for now. Apple needs to clarify its support for Intel's Virtualisation Technology (VT), which requires more than just a VT-enable processor and software like PD to run. Apple's firmware has to support it to, and at this stage it's not clear whether that's the case. PD can take advantage of VT if it's there, so it has the opportunity to become faster and still offer much better ease of use than BootCamp.


Which approach you take to running Windows on a Mac will depend on how you balance the performance you hope to get out of your system with your need to proceed safely and risk-free. BootCamp will always deliver the maximum performance to your Windows apps, but Parallels Desktop offers greater flexibility and an easier, safer installation process. It's also the better product for quickly dipping in and out of Windows - or any of the other x86-based operating systems it, unlike BootCamp, supports. ®