Power Requirements

As a corollary to the battery life tests, we also performed measurements of power requirements using the AC adapters and a Kill-A-Watt device. These numbers are only accurate to the nearest Watt, so a difference of 1W (i.e. from rounding) could obscure up to a 12% actual difference in power requirements. Also note that power requirements change when you switch to DC power, and power supply (power brick) efficiency comes into play when using the AC adapter, so the battery life tests are a better indication of true power requirements.

System Power Requirements - Idle

System Power Requirements - 100% CPU

System Power Requirements - Gaming

How's that for a nice exponential scale of power requirements? It's sort of fun to see the huge discrepancy in power requirements between desktop replacement notebooks and thin and light laptops. The most interesting aspect of the above graphs for most people will be the various power states of the UL80Vt. It looks like the CPU power requirements from Turbo33 are negligible at idle but can add up to 12W at full load. Meanwhile, the G210M GPU looks like it adds 3W at idle and somewhere around 10W at full load. (We can't be precise since the faster GPU also allows the CPU to work harder, contributing to the overall power draw.)

Battery Life - Gaming

As a point of reference, we also added battery life while "gaming" (looping 3DMark06 at native LCD resolution). The only difficulty is that the laptops provide different GPU performance levels on battery power; for example, all of the Clevo designs force the GPU into a "limp mode" where it runs at significantly lower performance (around the level of the G210M, actually). The two ASUS laptops we're looking at today both allow you to run at full performance while on battery power, so keep that in mind when you look at the last chart.

General Windows Performance LCD Quality (Stinks)
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  • whatthehey - Tuesday, December 15, 2009 - link

    Thanks for that; now go blow more smoke up Jobs' arse and leave the real discussion to people that can think.

    Calling this a cheapo Asus to try and make you Mac look better is pathetic. What makes it cheap, other than a plastic body? Most laptops are plastic shells, and this is still $40 less than the plastic MacBook while offering superior battery life and gaming performance. Plus I wouldn't have to put up with OS X and its quirks. Anand may love that stuff but I'd just as soon stick with Windows. No contest over glorified Apple.
  • KutterMax - Tuesday, December 15, 2009 - link

    Congratz to ASUS for the UL80Vt which looks to be a very nice portable machine that still has some pretty reasonable gaming performance coupled with great battery life.

    ASUS has made some great computers. I picked up a "Lamborghini" a few years back and still really like it. However the very short battery life and heft did not make it the best travel companion.

    I recently picked up a new Sony Z-series with a 2.8GHz processer, a couple extended batteries, and built-in Bluray. Granted it wasn't cheap, but the laptop is pretty slick. Sony allow put a great display on it and Blurays look outstanding. Importantly - it plays Torchlight great...
  • Basilisk - Tuesday, December 15, 2009 - link

    "... if you're talking a difference of 10W to 14W, that's a 40% increase in power requirements - or 40% less battery life."

    I believe the correct statement is "29% less run-time":
    RT = Wh / w ; RT reduction = 100% * (1-10w/14w) = 28.6%

    By analogy, your metrics would suggest a 100% loss in run time (= zero time) if the draw was 20 watts, whereas its actually a 50% reduction.
  • JarredWalton - Tuesday, December 15, 2009 - link

    Sorry... was being lazy when I wrote that. It would mean the lower power gets 40% more battery life, but as you point out the higher power draw is 29% less battery life.
  • Wolfpup - Tuesday, December 15, 2009 - link

    Notebookreview's forums have reported major stability issues with that specific model:
    http://forum.notebookreview.com/showthread.php?t=4...">http://forum.notebookreview.com/showthread.php?t=4...

    That's really uncommon for Asus laptops, but seems to be the norm for this model, so...I take it the review unit didn't have those issues?

    I run Folding @ Home on both my CPU and GPU when I'm not gaming or watching Blu Rays, so one way or another my hardware's always getting hit hard...need it to be 100% stable.

    Also, regarding Vista or 7 losing power settings, I've never had that happen, though I always use "always on" and always do a clean install of the OS (I wasn't running much Asus software on my N80nv on Vista, and didn't install any under 7).
  • JarredWalton - Tuesday, December 15, 2009 - link

    I didn't have any stability issues with the G51J during testing. That said, I highly caution against running Folding@Home (SMP or GPU) on a laptop. I used to do that and found that it seemed to cause serious problems after 6 months or so... that it just pushed the hardware beyond where it was intended. I sometimes wonder if all the "failing NVIDIA mobile GPUs" isn't somehow related to a lot of people running such apps, but that's probably oversimplified.

    In short, while I respect what the Folding teams are doing, I've determined that intentionally stressing hardware is a good way to make it fail sooner rather than later -- even if the hardware was once "100% stable". The benefit to me personally doesn't outweigh the cost... and if you're running a "folding farm" with desktops, your costs can very easily scale into the realm of $100+ per month for power, let alone hardware. :|
  • Wolfpup - Tuesday, December 15, 2009 - link

    Thanks for the info! Glad to hear it was stable.

    I guess my N80 is a guiness pig for Folding then. If it does fail, that'll force me to upgrade :-D
  • Glock24 - Tuesday, December 15, 2009 - link

    I'm currently frustrated because I want to buy a new laptop, but it seems every manufacturer only ordered 1366x768 screens, be it for 12", 14", 15.6", or even 16" or 17" laptops.

    I was seriously considering an Asus N81Vp, and the only screen available is.... you guessed it, 1366x768. My current laptop, an Asus F8Va has a 14.1" 1440x900 screen, so you may understand my disappointment.

    I think manufacturers are trying to squeeze every penny they can putting those cheap 16:9 screens on every laptop. They do not realize we, the consumers, also use our laptops to work and not just to watch movies.

    1366x768 is ok for a netbook, not for a real laptop.
  • strikeback03 - Tuesday, December 15, 2009 - link

    Seriously. The UL50 (15.6" version) sounds like a laptop I would consider, but not with anything less than a 1680x1050 screen and a decent contrast ratio.

    On a side note, has anyone had trouble with Win7 blanking their screen but not actually turning it off? On both my desktop and laptop after the "turn screen off after" time has elapsed, the screen will flick off then back on, and stay on but blank. Any way to fix this?
  • yacoub - Tuesday, December 15, 2009 - link

    Looking forward to a review of the new ASUS EeePC Seashell 1201N-PU17-BK. That's an interesting one - dual-core, ION, 12" display, etc.

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