Power Consumption

For power testing, we removed the battery from the laptop and measured system power draw at the wall outlet using a Kill-A-Watt device. All three laptops were configured to run at maximum performance when plugged into AC power. We tested under stress conditions as with the noise and temperature benchmarks, but we also added a couple more results. First, we have peak power draw, which is often quite a bit higher than the typical average maximum power. We then got a rough estimate of the average power draw under full load, as well as a maximum power draw when only the CPU is placed under full load using two instances of Folding@Home. Finally, we have idle power draw, where the system has been sitting with no applications running for 10 minutes or more. The screensaver is disabled, as is the hard drive sleep mode.

AC Power Draw - Peak Load


AC Power Draw - Average Load


AC Power Draw - CPU Load


AC Power Draw - Idle


Why would anyone want to get the X1400 in such a laptop? Obviously, because it uses far less power than even the GeForce Go 7800. While 10 to 12 W might not seem like a big deal, that represents 25 to 30% more power draw. Considering that the battery is rated as 80 WHr, a load of 20 Watts will last roughly 4 hours while 30 Watts will only last 2 1/2 hours. That's the theory anyway, so we'll turn to our battery tests to find out exactly how long the systems can run under typical usage.

We also tested power draw with the LCD at maximum brightness and minimum brightness. The total difference was only 6 W, indicating that the LCD manages to be very power efficient. There are eight brightness levels on the LCD, and power draw scales pretty much linearly as you go from level 1 to level 8. The default brightness when running on battery power is 3, although if you use the system in direct sunlight you will definitely need to crank that up. Going with the maximum setting will reduce your battery life somewhat, but you shouldn't lose more than 30 minutes of battery life at worst by setting it at maximum intensity.

Noise and Heat Battery Life
Comments Locked

34 Comments

View All Comments

  • Gary Key - Tuesday, May 30, 2006 - link

    Jarred will be reviewing these in the near future.
  • tthiel - Tuesday, May 30, 2006 - link

    I've been issued plenty of Dell laptops at the various companies I have worked for and they were all cheap plasticky junk. I've lost track of how many died on me. I was just given a new Thinkpad T43P and it is much better. Very well made, rock solid. So many of the engineers where I work wanted those instead of Dells that they had to restructure the ordering process and images to take care of all the new Thinkpads.
  • JarredWalton - Tuesday, May 30, 2006 - link

    I've heard about problems with ThinkPads now that Lenovo has taken over. (I haven't used any personally, so I can't say for sure.) I have also used many of the older Inspiron models, and have been unimpressed. These are definitely in a different league, however -- the cheap plastic case (at least on top) has been replaced by aluminum, for example. The problem is that most businesses don't buy higher end Dell laptops; they go with the more value oriented offerings, and whenever prices cut you can be sure that quality is cut as well.

    We're hoping to expand our mobile coverage in the future, so this is merely the beginning. As time goes on, we'll have more products that we can directly compare new offerings with. For now, I'm generally impressed with what the E1705 offers. Impressed enough that I recommended one to a family member, after browsing around looking for a suitable equivalent. Getting a large laptop with a 17 inch (or larger) display, 1920x1200 resolution, dual core processor, etc. is pretty difficult right now. Getting one with 2 GB of RAM for $2300 is even more difficult. Not everyone wants a laptop this large, certainly, but for those that do the E1705 is quite good.
  • jenson - Monday, January 7, 2013 - link

    when cheap laptops really got a good shake, with many models looking and behaving a lot more like their costly cousins than in the past.

Log in

Don't have an account? Sign up now