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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  • crydee - Wednesday, December 16, 2009 - link

    From reading other forums it sounds like the UL30VT has a nicer LCD and build quality. As soon as they start selling those and with the same battery as the UL80VT the price should be lower for an overall smaller laptop and no dvd-rom. That sounds like the laptop I'd want. 13" will be easier to handle the smaller resolution.
  • duffmann - Wednesday, December 16, 2009 - link

    On my ASUS UL30a (which also has a SU7300) there is an option to do a 1-5% overclock in the BIOS. By default it was set to a 3% when I recieved the system effectively making it 1.339GHz. Is this option also present on the UL80Vt and if so, do the "stock" numbers in the article correspond to 1.3GHz?
  • JarredWalton - Wednesday, December 16, 2009 - link

    I did not check in the BIOS (and the laptop is on its way back to ASUS), but CPU-Z/Intel TAT showed a clock of 1.30GHz at stock and 1.73GHz overclocked, so if there is a BIOS overclock option it was not enabled.
  • rubbahbandman - Wednesday, December 16, 2009 - link

    I got the Lenovo Ideapad Y550 over the holidays and think it should be considered as well if you're looking for a budget gaming laptop.
    For $820 (not including tax) I got:

    *Intel Core 2 Duo P8700 (only 25watt processor) vs i7 720QM (45watts for similar performance, and costs far more)
    *4GB DDR3 (pretty standard)
    *Nvidia Geforce 240M (23watt videocard) vs 260M (75watts)
    *320GB HD (5400 RPM, my worst part, but at least it's low power, quiet, runs cooler, and doesn't vibrate as much as a 7200)
    *HD LED 1366x768 native resolution doesn't seem like a disadvantage to me. It's comfortable for the eyes and doesn't require as beefy a videocard, uses less power too I'd imagine than 1920x1080. While the 240M offers far less powerful than the 260M, it good enough to play most games at 1366x768 with high settings and doesn't draw nearly as much power or produce as much heat as the 260M.
    *and it comes with bluetooth, wireless N, nice 'laptop' speakers (w/a tiny sub), win 7 64bit, hdmi, dvd writer, eSATA, 6 lbs, (no TV-tuner though).
    *with only a 6-cell battery I can surf the web for 4hrs 15min with my setup. gaming on the other hand is about 90min-2hrs, which is still very good compared to most.
  • bennyg - Thursday, December 17, 2009 - link

    There's budget midrange gaming and there's budget highend gaming, you're comparing quite different categories here
  • rubbahbandman - Thursday, December 17, 2009 - link

    "ASUS G51: Affordable Midrange Gaming"
    FTA
    I'm just pointing out there's affordable midrange gaming at less than $900 for laptops versus the $1400-1500 price tag for the G51. Neither of the computers in this article would be considered "high-end" for laptop gaming.
  • JarredWalton - Thursday, December 17, 2009 - link

    The only thing significantly faster in laptops would be something sporting dual GPUs (for now). GTX 280M laptops are about 20-30% faster at most in gaming, which isn't much considering the majority of such laptops will cost well over $2000.

    Mostly, I call this "Affordable Midrange" because I consider $1500 to be the top of the midrange laptop market in terms of cost. The GTX 260M is about twice the performance (slightly more) of the GT 240M: 96 vs. 48 SPs, and clock speeds that are marginally faster, with 256-bit vs. 128-bit memory interface. Also, if you're going to quote 23W for power on the GT 240M, the GTX 260M would only be 38W -- 82W is the difference I measured between system idle and gaming load, which is going to be split between the CPU, RAM, GPU, etc. (I also only show a 31W difference between 100% CPU load and gaming load, which corroborates that 38W figure from NVIDIA.)

    Of course, the GT 240M is going to be around 2.5 times the speed of the G210M in the UL80Vt, so you'll be able to run any game as long as you're willing to drop the details. Where the GTX 260M is able to run games at 1080p with medium to high detail, the GT 240M will be limited to 900p at ~medium detail.
  • Hulk - Tuesday, December 15, 2009 - link

    The flex results from the torque applied to the screen.
  • Wesleyrpg - Tuesday, December 15, 2009 - link

    As well all know Asus underclocked the GTX 260M in the G51J from the defaults of 550/1375/950 to 500/1250/800 for heat management issues, but im wondering how much extra performance can be squeezed out of the system by 'overclocking' the GPU to its default speeds and beyond. I'm also curious to know how this affect the systems temps!

    Can the Asus G51J take advantage of faster RAM like DDR3-1333 or DDR3-1600 modules? At what point does the machine start to gain/lose performance because of extra bandwidth/latency of the faster modules?

  • Wesleyrpg - Tuesday, December 15, 2009 - link

    ok so i did some testing and got some very interesting results, i ran 3dmark06 three time and here are the average results!

    10069 (500/1250/800)
    SM2.0 4417
    SM3.0 4036
    CPU 3179
    Temp min/max 64-91

    and now for the GPU running at 550/1375/950

    10983
    SM2.0 4854
    SM3.0 4559
    CPU 3191
    Temp min/max 64-92

    Thats it......a 10% improvement for a 1C in temp? Maybe im not getting the whole picture here or maybe Asus are downclocking for longevity reasons?

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