Gateway NV52 (AMD) - Battery Life
We'll start with AMD's mobile platform, which we have already dissected in previous reviews. Here's the quick rundown of specifications, and as much as possible we updated all applications, drivers, and OS components to the latest versions. The ATI drivers for Windows XP and Windows Vista are slightly older than the Windows 7 drivers, but unfortunately we are not able to install "reference drivers" on ATI-based laptops for Vista or XP. Thanks OEMs!
| Gateway NV5214u Test System | |
| Processor | AMD Athlon 64 X2 QL-64 (Dual-core, 2.1GHz, 2x512KB L2, 65nm, 35W, 667MHz FSB) |
| Memory | 2x2048MB Hyundai PC2-5300 @ DDR2-667 5-5-5-15 (Hyundai Electronics HMP125SEFR8C-Y5) |
| Graphics | Integrated ATI Radeon HD 3200 Driver version Cat 8.582-090203a (Feb 03, 2009) 40 (8 x 5) Shaders at 500 MHz |
| Display | 15.6" Glossy WXGA (1366x768) AU Optronics B156XW02 |
| Hard Drive | Seagate Momentus 5400.6 320GB 5400RPM 8MB (ST932032 0AS) |
| Optical Drive | 8x DVDRW (LG Electronics GT20N) |
| Battery | 6-Cell 10.8V, 4400mAhr, 47.5Whr |
| Operating System | Windows Vista Home Premium 64-bit |
| Price | NV5214u available at Best Buy for $500 |
We are comparing performance and battery life on a single system, so system specifications don't necessarily matter. This is an apples-to-apples comparison between several different operating systems using the same hardware. Here are the results.
So we have some good news and some bad news. The good news is that Windows 7 definitely shows some battery life improvements relative to Windows Vista. The bad news? We're still awaiting the official launch of Windows 7… and then we need to start from scratch with battery life testing on future laptops, since as we don't want to compare apples and oranges.
Using the Balanced profile, Windows 7 ends up providing 11% more battery life than Windows Vista. When we switch to the Power Saver profile, the margin of victory shrinks to 5%. The wildcard in these tests is Windows XP, which delivered the best battery life using its Portable/Laptop profile (by 2% over Win7, so it's almost a tie). However, it also achieved the worst battery life using the Max Battery profile (Win7 wins by 6%).
The margin of error between runs is around 3%, but we try to run each test multiple times and take the best result… unfortunately, when you have one laptop and about 30 battery tests to run on it, each requiring around four hours (with recharge time), repeating each test is a bit too much to ask for. Case in point, the Gateway NV52 originally had a score of 175 minutes on one run with the Power Saver profile, which seemed too high; rerunning the test three times showed that there must have been some other factor involved (i.e. perhaps a Flash ad server was temporarily down). Feel free to take the figures with a grain of salt, and we have some additional data later to verify the standings.
Clearly, power profiles are making a big difference depending on the operating system. Windows XP saw the least benefit, improving just 4.5% by using the power saving profile. Windows 7 comes in second, with an improvement of 13%. Then we have Windows Vista, which delivers an astounding 20% improvement in battery life just by switching the power profile.
Ubuntu is a little bit more difficult to assess, but clearly Ubuntu doesn't come anywhere near matching Windows. Using the power saver profile and Firefox, Windows Vista beats Ubuntu by 38%. Even if we factor in the power profile (Ubuntu doesn't appear to have a way to manage power profiles like Windows), that would still be a difference of around 15% in favor of Vista. Flash is extremely sluggish on Linux, however, and the margin of victory decreases when we use the FlashBlock add-on. At that point, Windows Vista only wins by 19%, which we could attribute to the power profile. That's still a significant difference in battery life, and we're using the worst of the Windows OS options for comparison. We didn't have time to test with other operating systems using Firefox or FlashBlock, largely due to the amount of time we spent trying to get Ubuntu to work properly in the DVD playback results.
The DVD playback results are completely different from the Internet battery life results, with the power profile having virtually no effect on battery life. The three Windows versions had the same score, within one minute, using each profile, so using the Power Saver profile is clearly no panacea. On the other hand, there are definite differences between the three Windows OSes. Ubuntu crashed repeatedly during DVD playback, sometimes to the point where we needed a hard reboot. Changing to the open-source MESA drivers fixed the situation with DVD playback, but under that test scenario Ubuntu manages a rather unimpressive result. It looks like ATI's drivers would last just over two hours with Ubuntu in DVD playback, so they definitely do better in terms of power optimizations. Looking at the Internet battery life with the open-source MESA drivers, there's clearly a lack of power optimizations (despite enabling dynamic clocks in the xorg.conf file).
Overall, Windows 7 appears to improve battery life for DVD playback by over 20% relative to Windows Vista, but the improvement is only about 6% relative to Windows XP. The story for Internet surfing is far more confusing. If you use the Balanced power profile, Windows XP beats Windows Vista by 13% and just edges out Windows 7 by 2%, making it the best option. Turn to the Power Saver profile and Windows 7 is the leader, 6% ahead of XP and 5% ahead of Windows Vista. Ubuntu isn't even in the running, with Vista offering up to 37% more battery life using Firefox; blocking Flash elements does help Ubuntu, but it also helps Windows and the gap shrinks to only 19%. Makes you wonder if Flash content is actually worth having, doesn't it?
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Veerappan - Tuesday, September 22, 2009 - link
I'm not sure if it's possible at this point, but if you can, would it be possible to try out a copy of the 9.10 Alphas that are available? They should hopefully fix some of the intel driver regressions.Also, as an FYI/diagnostic, there's a CPU speed applet that is available in Gnome. Right click the top panel, select 'add to panel', and then somewhere there's a cpu speed monitor. That can be used to see if SpeedStep/Cool'n'Quiet are working correctly. You can even take it a step further, and change the permissions of the applet to allow you to change which CPU speed governor is active if you find that the CPU is running at full speed constantly.
lyeoh - Tuesday, September 22, 2009 - link
By the way, you should not use external sites during your test. The fact that you said "perhaps a Flash ad server was temporarily down" means you are doing it wrong.Different flash ads could be very different in CPU usage.
What you should do is snapshot/save the complete pages loaded from the websites you want, put them on a standardized webserver under your control, and then get the browsers to load the pages from that webserver. Disconnect the test network from the internet to prove that the page loads up fine without requiring external connections (css etc). You may need to include a test DNS server that fakes the replies, or stick to using IP addresses to access the test pages e.g. http://10.5.5.1/site1/testpage1.html">http://10.5.5.1/site1/testpage1.html http://10.5.5.1/site2/testpage1.html">http://10.5.5.1/site2/testpage1.html http://10.5.5.1/site3/testpage1.html">http://10.5.5.1/site3/testpage1.html
Once you have standardized on a set of pages, this means you don't have to redo the tests on all computers weeks/months later when you have another laptop to test. You only need to test the new device - since the pages are the same. Don't change the webserver too much either (but given the low loads it's unlikely to affect things much - unless it's really really slow).
JarredWalton - Tuesday, September 22, 2009 - link
Already in progress, after my round two Internet testing still proved too variable. As noted elsewhere, though, I want the content to be as close to realistic as possible. Law of averages says that most of the ads will balance out. It's also possible my home wireless phone knocked out my home WiFi a few times, which would mean several minutes (more?) of non-traffic. Many times I'm not around while letting the battery drain, since that's a bit of a waste of time.I need a new home phone for sure, though. The 2.4GHz model I bought several years back wreaks havoc on my 802.11n network.
strikeback03 - Wednesday, September 23, 2009 - link
You need a home phone at all?JarredWalton - Wednesday, September 23, 2009 - link
Babysitters might need something to call us, yeah. Could leave a cell with them I suppose, but I also use it for business/fax.7Enigma - Wednesday, September 23, 2009 - link
I highly recommend the Uniden DECT6.0 models. The kit I got about 6 months ago to replace crappy old units was ~$110 for 3 units. Additional units (if your manion requires :) can be added easily to the setup for another $30-40. No wireless issues whatsoever. And it's the first phone I've been able to use out to my curb without issues (brick exterior with plaster walls = bad signal). The only gripe I have is there doesn't appear to be a way to change the caller ID name when it comes in. You can program your own numbers in, but when you receive a call it always shows only how caller ID recognizes it.Got mine from the egg.
mschira - Monday, September 21, 2009 - link
on my Atom based laptop. Flash is mostly used for annoying advertising. And it eats CPU, makes the budy slow.Booo to flash...
M.
dnd728 - Tuesday, September 22, 2009 - link
If Adobe merely added a button to freeze all Flash animations or even just freeze all Flash in non-active tabs, then like a hundred power plants could have been scraped…JarredWalton - Tuesday, September 22, 2009 - link
Which is what FlashBlock does. :) Of course, Linux browsers by default don't normally auto-play Flash I don't think. I enabled that with Firefox and then used FlashBlock to stop it, just for an "apples-to-unoptimized-apples" comparison to Vista.bigboxes - Monday, September 21, 2009 - link
Whatever. I use adblock plus and see few ads. Flash, however, is a part of how we view the internet. It's a part of our experience. If you want a text only internet please feel free to step back in the wayback machine to 1988.