Sign in with
Sign up | Sign in

Power Usage And Battery Life

The AMD A8-3500M APU Review: Llano Is Unleashed
By

Given AMD’s improved power efficiency claims, we’re naturally interested in Llano’s alacrity here. After all, AMD’s presence in the mobile space is modest. So it’ll take demonstrations of solid battery life to complement respectable performance if the company hopes to make inroads with mobile vendors perpetually pushing smaller form-factors and more run-time.

Our first test is the Tom’s Hardware Real Life Usage (RLU) benchmark, something our own Andrew Ku created. This test simulates actual use by Web browsing, performing Microsoft office tasks, and viewing a DivX movie.

Because we’re benchmarking two laptops with different batteries and screens, we’ve removed those variables by simply measuring power use when outputting to an external monitor.

Based on the chart, you’d expect that the A8-3500M APU would have the advantage over Intel’s Core i5-2520M in general power usage.

But Intel’s processor dips into a low power state more often. This mode-switching results in very similar power numbers. The Core i5-2520M averaged 12.8 watts during Web browsing, 17 watts during office tasks, and 19.4 watts in movie playback. In contrast, the A8-3500M averages 15.2 watts, 16.3 watts, and 19.5 watts, respectively. And while the Core i5 demonstrates faster CPU performance in our benchmarks, that isn’t as much of a factor when you’re surfing the net, typing a document, or playing back a movie. The experience is the same.

Now let’s see how these platforms handle a graphics load: 

The power use in the above graph is a result of a controlled test on an external monitor, so we repeated this metric again, this time using the laptop’s own display. The A8-3500M laptop lasted two hours and 12 minutes. Assuming the Intel laptop used the exact same battery, it would run for one hour and 22 minutes.

This is very impressive. Not only does the A8-3500M get about twice as much time out of its battery, it does so while delivering far better graphics performance. The implications of this are profound: a Llano laptop user might be able to play a mainstream 3D game for an entire two-hour flight with decent frame rates, while the Intel Core i5-based platform would only last for half of the flight with choppy performance. There does, in fact, seem to be validity in AMD’s excitement over its improved power story, and of course this is a real advantage when it comes to mobile devices.

Finally, we wanted to look into the company’s claims about AMD AllDay power. Now, AMD defines “All Day” battery life as 8+ hours in Windows, idling. This is ridiculous, plain and simple. Nobody powers on their system and lets it sit there just to claim it was on from nine to five at work. AMD needs to sit down and let the engineers do their thing. The real-world power figures tell a compelling-enough tale without some marketing-driven buzzword.

On our A8-3500M-based test mule, we did try to see how long the battery would last using the lowest monitor brightness and a very simple workload: document reading. We used the Battery Eater Pro benchmark to simulate someone browsing through a document and the machine lasted 7 hours and 40 minutes. That’s quite a feat for a full-sized laptop running an AMD processor, given the company's track record in the mobile space. The Sabine platform brings the fight to Intel's turf.

Ask a Category Expert

Create a new thread in the UK Article comments forum about this subject

Example: Notebook, Android, SSD hard drive

Display all 6 comments.
This thread is closed for comments
  • 1 Hide
    Jay_83 , 14 June 2011 12:42
    Hmm. Mixed feelings about this one. One the one hand, it's less impressive than I wished for. On the other, it's obvious AMD has done some good work here, in more than one direction.
    Ultimately, We'll have to wait and see what Trinity has to offer to give the final word. Here's hoping Bulldozer throws a serious punch. I'm sure we'd all like to see AMD back in the game, and not just in notebook space.
  • 1 Hide
    aje21 , 14 June 2011 21:50
    If you want us to look at this as the end of entry level discrete GPUs for light gaming, how about comparing it to the GPU running at its real speed? Once you have a real price for an APU+M/B you can put it up against a similar spec/price CPU+GPU+M/B to see how they compare.
    If the transcoding performance was worth having (and supported by Windows 7 in Media Center) then this could be an HTPC route...
  • 3 Hide
    daglesj , 14 June 2011 22:04
    Chaps, you are wasting your time commenting on the UK version of the article. All the comments are over on the US version.

    Why they cant pull the 'shared' article comments together I dont know.
  • 1 Hide
    Anonymous , 15 June 2011 09:22
    Seems like the Turbo CORE was simply turned off... Perhaps it needs more than enabling it in the BIOS. Like in case of Cool'n'Quiet, that you has had to enable in Windows, as well?
  • 1 Hide
    silverblue , 15 June 2011 19:36
    ajaraSeems like the Turbo CORE was simply turned off... Perhaps it needs more than enabling it in the BIOS. Like in case of Cool'n'Quiet, that you has had to enable in Windows, as well?

    Yeah, by selecting Minimal Power Management in XP or Balanced in Vista/7.
  • 0 Hide
    wild9 , 24 June 2011 23:31
    daglesjChaps, you are wasting your time commenting on the UK version of the article. All the comments are over on the US version. Why they cant pull the 'shared' article comments together I dont know.


    I've often thought the same..I wish all the UK and US comments could be combined. I discovered the duality by accident, and also noticed that the UK version of the article has 4 comments, whereas the US had 4 pages. I am grateful for all this tech news..I just wish the comments section could be combined. Also, if they could send the spammers to Mars..that would be a nice bonus.