Traditionally, Microsoft has been a dominant force in the computing landscape, and with that domination it has cultured partnerships with many companies to have them build PCs based on Windows. Practically every computing device sold came pre-installed with the current version of Microsoft’s operating system, with the price of the OS factored into the overall cost of the device being sold. People wanted PCs, and those PCs were running Windows, so the partnership flourished. The only real competition came from Apple, but Apple was not interested in the tight margins created by the stiff competition for the lower cost PC, and Windows was left to monopolize the market.

Several major changes occurred over the course of the last several years which have certainly impacted overall Windows license sales – the meteoric rise of Android being the most powerful one, but another major shift was Microsoft changing its position as a seller of software to that of a hardware maker, directly competing with its long established partners. Microsoft of course had one major advantage over its partners in that it didn’t need to factor the cost of Windows into the Bill of Materials (BOM). This has certainly been a factor in the recent move by every single OEM which traditionally focused on Windows devices to broaden their efforts and begin providing devices based on competing operating systems – namely Android and Chrome OS.

Both Android and Chrome OS are free, which means a lower BOM, and inevitably a lower device MSRP.

Low cost computers
Chrome OS (Base Config) Acer C720 Samsung Chromebook 2 HP Chromebook 11 ASUS Chromebox
Form Factor 11.6" Laptop 11.6" Laptop 11.6" Laptop UCFF Desktop
CPU Celeron 2955U Exynos 5 Octa 5420 Exynos 5250 Dual Celeron 2955U
Memory 2 GB 2 GB 2 GB 2 GB
Storage 16 GB 16 GB 16 GB 16 GB
Price $199 $319 $279 $179
Android (Base Config) Dell Venue 7 Samsung Galaxy Tab 4 Lenovo Yoga Google Nexus 10
Form Factor 7" Tablet 7" Tablet 10.1" Tablet 10.1" Tablet
CPU Atom Z2560 Snapdragon 400 quad-core MediaTek MT8389 Samsung Exynos 5 Dual
Memory 2 GB 1.5 GB 1 GB 2 GB
Storage 16 GB 8 GB 16 GB 16 GB
Price $150 $199 $275 $399
Windows 8.1 Devices Dell Venue 8 Pro ASUS T100 Acer Aspire V5 HP 110-220z
Form Factor 8" Tablet 10.1" Tablet/Laptop 11.6" Laptop Tower Desktop
CPU Atom Z3740 Atom Z3740 A4-1250 Kabini E1-2500
Memory 2 GB 2 GB 4 GB 2 GB
Storage 32 GB 32 GB 500 GB (Hard Disk) 500 GB (Hard Disk)
Price $299 $349 $329 $299

This is certainly not the first time Windows has had to compete against a free operating system. Linux, while powerful, has struggled to gain any traction in the consumer OS space, but briefly with the beginnings of netbooks Linux was installed as the OS. Microsoft quickly countered that with a lower cost version of Windows XP for devices categorized as netbooks, which quickly dominated that market as well.

But this time is not like the rise of netbooks. Android is a powerful platform, with a multitude of apps available, meaning people actively seek it out, rather than settle on what came with the netbook. Chrome OS too, while certainly more limited in scope than Windows, is a polished OS which is being constantly updated. Many people who simply require a device to go online, and maybe perform some basic tasks, don’t need or want the complexity of Windows. Also, the low system requirements for both Android and Chome OS, as well as the free nature of the operating systems has allowed OEMs to manufacture devices for less, and therefore sell them for less than a comparable PC. Lower prices obviously drive sales, and it’s worked.

At Microsoft’s developer conference BUILD, a new update to Windows 8.1 was announced. One of the goals was to lower the BOM for Windows devices by reducing the required memory to 1 GB, and reducing the required storage to 16 GB. Also, it was announced that Windows (including Windows Phone) would be free for all devices with a screen size of less than 9”. Clearly the goal was to compete directly with the low cost Android devices that were becoming ubiquitous in the market. Today it was discussed on the Windows Experience Blog that a new OEM only Stock-Keeping Unit (SKU) of Windows would be available called Windows 8.1 with Bing.

Now, before you get concerned with the name, it won’t be marketed to end users as Windows 8.1 with Bing – it’s just the name of the SKU. The only change between this SKU and the standard Core SKU of Windows 8.1 is that Bing must be the default search engine in Internet Explorer. End users can of course still change the default search engine to whatever they like, so really the only change here is a requirement on OEMs for initial setup.

But how were the system requirements lowered?

To get to 1 GB of memory space as a minimum, the app store frameworks were refined, and the process lifetime manager is more aggressively suspending apps, as opposed to killing them. This is tweaking existing processes to make them more efficient, but the bigger story is how the storage requirement was dropped from 32 GB to 16 GB. The answer here is an entirely new way to run Windows directly off of a compressed WIM file, in a system known as WIMBoot.

Previous to Windows 8.1 Update, an installation of Windows actually included two copies of Windows – one compressed version for recovery, and once again in the uncompressed form which is the files Windows runs on. Clearly this isn’t the most efficient way to run a system with a limited amount of storage, and one of the first tips for anyone with a 32 GB Windows device is to move the recovery image from the internal storage to an external USB drive. A standard Windows partition layout would have looked like this:

With new devices based on 8.1 Update, Microsoft has taken the opposite approach with WIMBoot – rather than remove the recovery partition, remove the uncompressed files and run directly off of the image file. In the place of the uncompressed files are a set of pointer files which point back to the compressed install file called install.wim. Also included are the Windows RE recovery tools, stored as winre.wim, and an OEM specific custom.wim file. This leaves a partition layout of this:

The custom.wim file allows an OEM to quickly update images, by just replacing the custom.wim file. This file is for final customizations such as Windows updates, build-to order apps and drivers, and other requirements of the OEM.

If an end user does a refresh on their device, the pointer files for the install.wim and custom.wim file are reset, making this a much faster operation than before.

The end result is a significant reduction in the amount of space Windows requires.

WIMBoot is available for all versions of Windows – x86, x64, and ARM, but it does require UEFI as well as solid state drives or eMMC. Traditional hard drives, or hybrid drives, are not supported likely due to performance.

It’s unclear if there is any performance loss or gain from running on the WIM file rather than uncompressed files, but it’s certainly something I’d like to test. If the performance hit is small, it would be surprising if WIMBoot doesn't expand past the low cost devices to cover the entire range.

With these changes, Microsoft is hoping to kickstart a resurgence of Windows devices at the low end of the market. With the lower BOM, OEMs should be able to be price competitive with Android and Chrome OS now, but with a Windows experience.

Source: Microsoft

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  • Ryan Smith - Saturday, May 24, 2014 - link

    Thanks. Fixed.
  • BMNify - Saturday, May 24, 2014 - link

    if WIMBoot (or even windows uncompressed) cant be installed and run (and it cant) from the masses of cheap generic USB3 hard drives on the market today what good is it !, also the fact that windows costs $50 but costs me £70<>£100 rather than the real current 29.71 British Pound Sterling plus VAT today, then again ,why pay the extortionate price hike (even on MS.UK web site) for windows , when you can install a free Linaro linux/android and boot from anything that's available at boot time to select at will.
  • name99 - Saturday, May 24, 2014 - link

    It's interesting to compare with how Apple solved the same problem.

    (a) For the recovery part of the problem, Apple doesn't provide the entire OS. What's provided is a small stub (650MB in size) which is large enough to run common tasks (most relevant here would be fsck), with the fallback solution being to reinstall the OS from the internet. Apple's assumption is that
    - users have internet available and
    - users are using Time Machine,
    so between the two of these, all that's really needed is enough to allow these to be activated. This seems to be an accurate assessment. In spite of the usual bitching about theoretical problems when the feature was first introduce, in practice I've seen precious few real world problems with the system.

    (b) For the saving space part of the problem, Apple did something similar to what MS has done here. They introduced transparent file compression. Obviously this had to be done in a way that was backward compatible (given that Apple didn't introduce a new file format with 10.6 when this arrived).

    The way it works is that the blob on disk is automatically decompressed whenever it's read --- just like normal transparent file compression. (You see this effect if you run rsync --- you'll see stretches in the rsync process where the data being written is 2x to 4x as much as the data being read from the src disk.)
    The cute part is that the only files that are compressed are those related to the internals of the OS. The idea is that if I take my drive with a copy of 10.9 on it (along with a bunch of personal files) and open it on a 10.5 machine, the personal files will open just fine. And yeah, if I open any system file, I'll get incoherent garbage --- but what did you expect? That's no different, conceptually, from Apple just changing the file format of data files from one version of the OS to the next, which is quite reasonable and which they have done both for plenty of small files as well as wholesale with the replacement of text plists with binary plists.
    This was done (along with a whole bunch of other stuff, like ruthlessly purging the system files of as much 32-bit support as possible, and making printer drivers, which were a mull-GB part of older OS installs, downloadable on demand) to support the small disks of MBAs, so same sort of motivation as MS.

    When we finally get the mythical and long-awaited HFSZ, with pools, end-to-end CRCs, multiple on-volume catalogs, and other such desiderata of a modern file system, I expect compression will be one of the features built available from the beginning and we won't need the compression to be quite so hidden (meaning, eg, that rsync will no longer only see, and have to store, the uncompressed version of files).
  • Divide Overflow - Sunday, May 25, 2014 - link

    To be followed soon thereafter by a marketing statement from Microsoft triumphing in the recent increase in end users "choosing" their search engine.
  • lorribot - Sunday, May 25, 2014 - link

    If you have ever tried updating a wim file with drivers or patches it takes a life time even on an SSD so not sure how that would affect things, maybe they have a quicker way to directly access individual files in the wim rather than open the wim, it would be good to see that technology in their Windows Admin Kits it could certainly make managing Windows images and distributing images in the enterprise space a lot more efficient and simpler.
  • pugster - Friday, May 30, 2014 - link

    Looks like they are trying to make a crappy version of windows 8.1. Too bad that this OS is not as modular as android.
  • amitsen88 - Sunday, July 6, 2014 - link

    IE with Bing is good.

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