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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  • ssj4Gogeta - Wednesday, May 6, 2009 - link

    Exactly what SkullOne said. I also use Linux and know in what areas it's better than Windows. But I also know there are so many other areas in which it's a pain to use.
  • SkullOne - Wednesday, May 6, 2009 - link

    Spoken like a true jaded Linux fanboi. People like you are the reason Linux will never be mainstream. You think you're so high and mighty (or more secure) when you're not.

    Thanks for the laugh. I'd love for you to back up ANY of your comments with facts.

    Disclaimer: I use Linux and Windows every day in production environments. They both have their place in the world.
  • snookie - Wednesday, May 6, 2009 - link

    This blaming of Microsoft's Vista woes on Apple and a few commercials is just ridiculous. Most people pay no attention to such things those few that see them. It also has nothing to do with why Vista was a flop in the consumer space and an even bigger flop in the corporate marketplace. Certainly nothing to do with so many companies offering XP downgrades. Vista is a lousy product plain and simple and if there is any marketing fault it is Windows with their arcane multiple editions at ever increasing prices designed to milk customers. People aren't stupid even if they are computer novices. They know when they have been had, something is difficult to use, or not reliable. This is the result of years of piling layer upon layer of code on an ever expanding code base with no effort to start over and offer a clean efficient OS. The ONLY thing Windows 7 has over Vista is the interface is simplified and gets out of your way better. It can SEEM to run faster all it wants but test after test shows Windows 7 is barely faster than Vista at many tasks and in fact slower at some. Microsoft is in real trouble here because years of cruft code have left a huge amount of unusable code that consumes resources, adds instability, and provides entry to all sorts of malware. There is no way this codebase can be made to work efficiently with the quad and higher core procs that will be even more common in the next few years and what is Microsoft going to do then? They have three failed ad campaigns under their belt so their years of lying to their customers has fallen flat and corporate customers long ago stopped believing anything Microsoft said which is why open source that doesn't lock you in is becoming more and more prevalent. Microsoft has met the enemy and it is them.

    I notice you run Microsoft ads btw.
  • ssj4Gogeta - Wednesday, May 6, 2009 - link

    I know so many people who haven't even TRIED Vista once and they keep telling other people how bad it is.
  • formulav8 - Wednesday, May 6, 2009 - link

    I agree almost 100%. I have customers who wants to make sure they have/get windows xp because vista is so bad. If you ask them why, they basically say its because a friend of a friends father said it was slow.

    I do know one of the biggest downfalls for Microsoft and Vista was allowing Intel to pressure them into getting Vista Certified compatability with those trashy integrated chipsets of Intel. So many users have those trash Intel xtreme/gma video chipsets and they had very bad Aero interface performance.

    Anyways, I use both Vista and Windows7 daily. I like Vista better than XP overall and like Windows7 thus far compared to Vista.

    I really think Windows7 will end up being one of the best oses made, even when compared to osx and windows xp.


    Jason
  • vectorm12 - Wednesday, May 6, 2009 - link

    Personally I never took to windows XP nor vista(had it been tecnologically possible I would still have been on WinNT 4.0), however as I bought a new PC I hit the RAM cap of 32bit XP Pro and therefore felt I had no decent choice than to move to 64bit Vista.

    My Vista experience has been far from great, reinstalls, crap drivers from nVidia and ATI not to mention a bunch of other third parties. However it hasn't been all bad, vista has quite a few ideas that just didn't work out just the way I would have liked.

    Look at the save file dialogs for example where you actually had to click a button to browse directories other than the default one.

    I've now been running on Win7 x64 since build 7k reinstalling almost every time a new version has been leaked and I'd say most of the things that bugged me with Vista has been corrected.

    At this point the only thing I still want for Win7 is the "old" style control panel and an integration of the "administrator tools" into the control panel.

    Looking at the big picture I say Win7 (even in BETA) is the best modern OS Microsoft has produced. The performance issues of Vista have been dealt with to a large degree. Drivers seem to work better and the most annoying GUI issues have been dealt with.

    All Microsoft can do now to make me feel completely satisfied with my computing experience over the last few years is give me a BIG rebate on the upgrade to Windows7 from my old Vista licence.
  • johnsonx - Wednesday, May 6, 2009 - link

    I just upgraded my XP-era Vista box (2.2ghz single core A64, 2GB RAM, VIA AGP mobo, X1950Pro) to Windows 7 tonight, and it was absolutely painless. It certainly seems faster than Vista, in particular I notice that my e-mail client and web browser launch and become ready much more quickly.

    I'm finding the new UI features to be actually useful as well, rather than Vista's pointless eye candy. I often have 6 or 7 browser tabs and several e-mail windows open, along with another couple of apps, and the new task bar makes it much easier to switch among them. I can see if I have any new e-mail just by moving the mouse over the client icon on the taskbar, no need to even click on it. Aero-Peek makes gadgets more usable too, since you can see them without minimizing every window. AeroSnap is great too. Only AeroShake defies explanation, but perhaps time will prove that one too.

    I was never a Vista hater, though it certainly had it's frustrations. But it only took me 20 minutes with Windows 7 to never want to touch another Vista box again.

    I was initially concerned that ATI's Windows 7 driver only supports cards back to the HD2000 series (presumably because the WDDM 1.1 driver model requires DX10 class hardware, which my X1950Pro is not), but the MS provided driver had no problems with Half-Life 2 (the only game I happen to have installed on this box) or any of the fancy GUI features.

    The only weirdness so far as that at last boot up Windows told me a driver for Trend Micro Internet Security was being blocked due to a compatibility problem with Windows 7. That's understandable, except for the fact that I don't have any Trend Micro product installed, nor has one ever been installed in the past. It wouldn't tell me exactly what driver it was complaining about though, so I can't investigate further (I suspect some log somewhere will tell me exactly what driver it blocked).

    One taskbar UI incontinuity: so much now works by simply moving the mouse over the various items, it suddenly seems odd to have to actually click on the start menu to get it to open.
  • johnsonx - Wednesday, May 6, 2009 - link

    ok, it turns out the offending driver was TMCOMM.SYS, and it really was from Trend Micro. I have a vague recollection of running an online scan once a couple years ago (trying to scan a friend's external drive), so I guess it was trend micro and it left that driver around.
    As with most such things, the blocking event was neatly logged in the system event log.
  • thebeastie - Wednesday, May 6, 2009 - link

    Wow, this new OS looks like Vista but with all the latest patches,IE8 and DirectX11. Then just a few cosmetic graphics changes.
    I AM EXCITED!
    Come on what else did you expect? Maybe its something that has stuck deep in side people since they were kids around new PCs but when it comes to Microsoft new OSes people are just getting more and more nieve.

  • thebeastie - Wednesday, May 6, 2009 - link

    More tests appear to be slower in Windows 7 then Vista etc.
    Things like reltek sound performance can be put to just as much to the 3rd party drivers then anything else.

    I can't believe how many people I have talked to that use but hate Vista and expect Windows server to be light on its feet as XP but with the features of Vista, they are behaving as its something they could bet their life on.
    What does it take for people to get some some technical intuition?
    I mean thats what people really really really need here.

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