What about battery life?

It doesn't look like Windows 7 is going to be any more power friendly than Windows Vista when it comes to power draw on desktop systems. However, that doesn't necessarily mean there won't be improvements for laptops. Microsoft has a white paper detailing some of the changes.

One item where users do have more control than in Windows Vista is in regards to LCD dimming. You can now set the delay and brightness level that your LCD will dim to before turning off completely. Some users might prefer that to seeing their screen go black if they are just pausing for a couple minutes. In terms of the true impact of this feature, however, there hasn't been any significant change that we can test in a fair way. Obviously, running your LCD at a lower brightness level will require less power, but we standardize our laptop testing at 100 nits in order to keep things equal.

What about other power saving features? A section on the idle power requirements states: "Idle efficiency is critical for the overall battery life of a PC because idle time dominates most scenarios. Reducing idle power consumption reduces the base power consumption. For example, if a portable computer uses 12W when the system is idle, all other scenarios increase power by some amount over the base 12W. Reducing idle power consumption benefits all other end-user workloads and scenarios, from DVD playback to office productivity." That makes sense, and Microsoft goes on to state, "Windows 7 provides greater idle efficiency by reducing (and in many cases eliminating) background activity on the system."

Windows 7 is supposed to improve laptop battery life by reducing CPU power requirements. One way this is accomplished is by keeping better track of what is going on in the system and reducing processor activity so that it can enter lower power states. They even claim, "In-box support of these technologies enables power-saving benefits immediately after installation." Immediate power saving benefits? If they can actually live up to that claim on the shipping version, that will be excellent. Other power saving features focus on additional peripherals, with specific mention made of networking, Bluetooth, and audio components.

With the information from the white paper in hand, we decided to conduct some power tests on three different laptops. Laptops were selected in order to cover the three primary graphics chip suppliers: NVIDIA, ATI, and Intel. For the Intel system, we used a Gateway M-7818U 15.4" notebook with GMA X4500 graphics, and the ATI system is Dell's Studio XPS 16 with Mobility Radeon HD 3670 graphics. We tested both of these systems with an OCZ Vertex 120GB SSD and a 320GB 5400RPM HDD. Finally, the NVIDIA notebook is the recently reviewed MSI GT627 featuring NVIDIA GeForce 9800M GS graphics. So let's take a look at the results....

Where's my chart!?

...or not. Simply put, we did not see any benefit to using Windows 7 at this point in time in regards to battery life, and in fact most systems had slightly lower (by a couple minutes - within the margin of error) battery life under Windows 7. We had hoped that the MSI GT627 would fare better than the laptops with ATI and Intel graphics, since NVIDIA just released their beta 185.81 driver; however, that was not the case. In fact, of the three tested notebooks the MSI GT627 fared the worst, losing six minutes of battery life relative to Vista (a change of 5% in the wrong direction).

We only had time to conduct testing utilizing our Internet battery test, so it's possible we will see improvements in other tests. Multimedia in particular has potential for improvement, as Microsoft mentions that they have invested extra time in reducing power requirements for multimedia workloads. For now, we will reserve final judgment until the shipping product.

Several notebook manufacturers have indicated that in internal testing they are seeing battery life improvements of 3% to 5% with Windows 7, and they expect with further optimizations that they will see as much as 11% to 13% better battery life relative to Vista. So what's missing right now? Microsoft's white paper again has the likely answer: "Energy efficiency requires investments across the entire platform, not only in the core hardware or in the operating system. While Windows 7 can have a significant impact on platform energy efficiency, attached devices, and non-Microsoft and end-user applications, other platform extensions often have a larger total impact. The complexity and quantity of platform extensions require a broad approach to energy efficiency beyond focusing on a single component in the platform." In short, the laptops need more optimizations focused on power management.

We have done "virgin" installations of Windows Vista on notebooks in the past, and battery life is generally worse than if we test with the laptop as it comes configured by the OEM. Some OEMs are good about providing downloadable drivers and utilities so that you can duplicate the original configuration, but right now with Windows 7 we are stuck with whatever Microsoft provides on the release candidate DVD (or through Windows Update). Hopefully the various notebook manufacturers are paying attention to this area and will have the necessary drivers and other utilities in order to get the most out of Windows 7's power management features.

Power Consumption Networking
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  • izal169 - Thursday, July 2, 2009 - link

    development of the technology is quite rapid. My computer specifications are not strong for Windows 7 that high quality. specification of my computer, intel core 2 duo, 1 Gb RAM, VGA Nvidia 7300 GS. microsoft is very cool. can make the OS with a relatively quick time.
    http://duitol.com/stop-dreaming-start-action/">http://duitol.com/stop-dreaming-start-action/
  • deteugma - Friday, June 5, 2009 - link

    I was an XP diehard until I installed Windows 7. Now I'm a convert and a proselytizer. I love Windows 7. It will be the first version Windows that I actually buy for myself, rather than accept for free from a family member's employer (university license). MS won't have trouble winning converts from the diehard crowd.
  • Biomorphic - Wednesday, May 27, 2009 - link

    Windows 7 has software based audio processing just like Windows Vista and my question is, will VXP enable hardware based audio processing or will it remain software based?
  • PC Reviewer - Monday, May 18, 2009 - link

    it looks alright as long as its performance is as good as, if not better than xp's. Im looking to do a review about Windows 7 on my blog soon aswell. http://www.pcreviewer.org">http://www.pcreviewer.org
  • alon - Sunday, May 17, 2009 - link

    First, I did not read all the comments, so if this has already been stated, I do apologize. For that matter, after the "Standard Test Bed" page I stopped reading the article. So .. maybe these issues have already been discussed.

    1) OK, so Vista x64 SP2 was released around May 11th (at least for my MSDN subscription, possibly earlier for others?) And it appears that the Windows 2008 SP2 bits were released around May
    14th. I still don't see an SP2 installer, but I can do a clean install with SP2 already slipstreamed. So ... I've looked and looked, but I can not find an XP Pro x64 SP3 anywhere. And according to Microsoft around last September, there was not going to be an WinXP Pro x64 SP3. So ... if you do have this SP3 around ... please let me know what MSDN/TechNet or whatever subscription you have so I can upgrade mine ... or point me to the release page.
    2) Concerning corporate IT ... one of the issues mentioned at the beginning of the article is the computing resources needed to run Vista ... which to me alludes to the fact that many companies chose not to upgrade to Vista based on HW requirements (of course Vista without Aero can run on many "lower" configurations, but of course the average company employee does not know this). I digress ... your test bed platform is not really anything that CorporateIT depts will be deploying. Core i7 ... released 7 months ago ... 6GB RAM. Please ... if you are going to try and "proove" that performance is decent with Windows 7 ... at least run some test systems that are not the toys we dream of, but the systems that are installed in the office. Until Microsoft and folks like you understand that companies can not afford to always buy new HW, the new OSs have to run on the last generation technology (actually more like HW from 2 years ago) ... your comparisons and results are useless ... and my 18month old Lenovo T61 does exactly what I need it to do. So, there would be no reason to upgrade to Win7 until MS End-of-lifes WinXP.
  • Razer2911 - Wednesday, May 13, 2009 - link

    Moving on from Vista 32, I have to say i'm impressed. There are very subtle changes and tweaks which actually make the experience better. A simple example would be the new taskbar, Jump lists and Aero peek feature. I for one dont like a million windows open on my desktop, somehow i always found it cumbersome and cluttered but within a couple of hours of using Windows 7 i found myself using 10-15 windows without getting bothered by the clutter. Never used a Mac but these new features actually have both form and function.
    One thing that i have not been able to figure out as yet is that all my videos (divx) and movies look very grainy and slightly pixelated on WMP 12 and VLC.
  • tomb18 - Tuesday, May 12, 2009 - link

    Support for canadian television in canada has always been limited in Media Center. Since HD digital over the air broadcasts (atsc)became available in the US, this has been supported in Media Center but not if you lived in Canada. Digital tuners are DISABLED by media center in all versions including Windows 7. This is in spite of the fact that canada uses the same ATSC system as the US. Many hacks have appeared but they always seem to be disabled by updates. This continues in Windows 7. As soon as the software determines that you reside in Canada, it disables the ATSC tuner.

    But get this. South Korea uses the same ATSC standard and it IS supported in that country.

    There are a lot of forums (such as the green button, run by the media center developers)that discuss this to no avail. No amount of questions, emails, or anything will get a comment from Microsoft. Even when MSVP's try to take up the battle nothing gives.

    There has been a lot of hope for Windows 7, that it would finally be supported, but alas, it is the status quo. My question is will Microsoft give a warning about the version of Windows 7 that contain media center for the canadian market telling canadians that their digital tuners will not work?

    I really wish that some website with industry influence (hint...hint) would expose this pointing out to the canadian market that they should not buy Windows 7 if they want to use the media center.
  • AnnihilatorX - Tuesday, May 12, 2009 - link

    Replace the function of minimising other windows with one that makes the window being shaked always on top. Now this is a useful function.

    Nevertheless I have been using AutoHotkey (automation programming platform) to assign Alt+z hotkey to make windows always on top in other windows. This is a feature I can't live without, along with Windows key + Scroll wheel on mouse to change transparency. These had help me multitask with different windows very efficiently.
  • rasmasyean - Sunday, May 10, 2009 - link

    I think people might have over-estimated Vista as the OS that will sweep across the world and change computers as we know it over-night. It didn't exactly turn out as expected, but I don't think it doesn't seem it did too bad.

    Gartner research report predicted that Vista business adoption in 2008 will actually beat that of XP during the same time frame (21.3% vs. 16.9%)[80] while IDC had indicated that the launch of Windows Server 2008 served as a catalyst for the stronger adoption rates.[81][82] As of January 2009, Forrester Research had indicated that almost one third of North American and European corporations have started deploying Vista.[83]

    http://en.wikipedia.org/wiki/Windows_Vista">http://en.wikipedia.org/wiki/Windows_Vista
  • compuser2010 - Sunday, May 10, 2009 - link

    "Never underestimate the power of marketing – many people can tell you they don’t like Vista, few can tell you why."

    I don't like Vista primarily because of built-in Digital Rights Management (DRM). Any time I need to capture, edit and/or transcode audio and/or video, I need to go back to XP.

    I have confirmed this with the following programs:

    Audacity 1.2.6
    Canopus EDIUS Broadcast 4.61
    Creative Labs Smart Recorder 2.40.23
    Moyea FLV to Video Converter Pro 2
    Ulead DVD Workshop 2

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