Gaming laptop with lowest power consumption ?

[NiHaoMike]

I just finished measuring the power usage of my laptop while playing mariposahd.tv using software decoding and Hannah Montana hardware decoding. Software decoding used 32w while Hannah Montana used 34w, so it may seem like Hannah Montana uses an extra 2w. However, the video quality was noticeably improved, so it actually isn't easy to say. I, however, think the extra 2w is worth the increase in video quality, so in my opinion, Hannah Montana wins.

Another interesting observation is that software decoding upclocked the CPU to 1.6GHz from 800MHz, but the video card (including the Hannah Montana core onboard) remained at 130MHz. Hannah Montana hardware decoding caused the video card to upclock to 475MHz, but the CPU remained at 800MHz.

Note that I did a "dummy run" before recording any measurements to avoid inaccuracies due to caching. The first time the file is accessed, the data must be accessed from disk, but the second time, the data will likely be cached in RAM. RAM uses less power than the hard drive, so caching can skew the measurements if it isn't accounted for. (Note that the first run will incur the power used to read the file from disk *and* write it to available cache, so it would be quite a skew!)

[Cd]

Ignorance is bliss as the saying goes....and ignorance can be amusing at times as well.
I noticed that you mentioned Hannah Montana, and thought " What the hell is he talking about ?? What does Hannah Montana have to do with computers ??"





Jokes on me I guess.

Thanks for all the info. What is the make and model of your laptop ?

[NiHaoMike]

It's a Dell Vostro 1700. The Nvidia 8600m GT in it has a Hannah Montana DSP core like all 8 series and above video cards. (Technically, Hannah Montana has existed in video cards since the 4 series, but that was an older core that could only perform very basic tasks like MPEG1/2 decode and 2D video effects. The newer core is much more capable.)

As for the details about Hannah Montana, read my previous post and http://www.mobilitysite.com/boards/w...ach-other.html .
What is particularly relevant to ecomodding is:

A diesel engine runs at much lower RPMs than a gasoline engine. Does that always mean the gasoline engine would have more horsepower? GHz is like RPMs, processor architecture is like engine design, number of ALUs is like number of cylinders, and number of bits is like displacement per cylinder.

Comparing that Core 2 Duo to a Pentium 4 is like comparing a turbocharged 8 cylinder diesel truck engine to a 2 cylinder racing motorcycle engine. Comparing either one to a Hannah Montana is like comparing them to an engine with a very large number of tiny cylinders, turning very slowly, yet still managing extremely good fuel economy in the right application.

So a good way of thinking about it is if you have a car with two engines, each one tuned to run efficiently under different operating conditions, but both must be running for the car to work. Under a given operating condition, you can choose to load one engine or the other (while leaving the other one more or less idling). Choosing to put the load on engine 1 uses slightly more fuel than putting the load on engine 2, but using engine 1 makes the car significantly faster. Which means that the slight fuel economy decrease can be justified by the faster speed. It's far from a perfect analogy since both processors and engines have complex operating dynamics that are not analogous with each other, but hopefully it helped you understand.

[rmay635703]

Originally Posted by Cd

I know that the Macbook Pro has a decent graphics card and uses an average of just over 33 Watts while processing, however, it's pricing is just stupid. You pay a premium for ... what ?

Any advice ?


BTW, A Playstation uses over 200 watts while you play your game, so one of these is completely out of the question.

I have a Tandy T100 it lasts for what seems like forever on a pair of AA batteries, you can even kludge a couple of text based games on it with a little effort. Plus more importantly you can type and send emails on less than 1 watt of green/blue screen power.

If people would do things that were actually important with their PC systems like posting to this message board they could get by with antiques, heck I have posted here using a 5Mhz IBM 5150 8088 w/640k just because I can It did take a while though to get the message through.

[NiHaoMike]

There are a lot of modern low power CPUs that use even less and are surprisingly capable.

TI's OMAP is fast enough to compete with lower end PC CPUs. Their DaVinci is fast enough to encode 1080p x264 in realtime. None of them require heatsinks and the insanely fast DaVinci just feels very warm to the touch.

[rmay635703]

Originally Posted by NiHaoMike

There are a lot of modern low power CPUs that use even less and are surprisingly capable.

TI's OMAP is fast enough to compete with lower end PC CPUs. Their DaVinci is fast enough to encode 1080p x264 in realtime. None of them require heatsinks and the insanely fast DaVinci just feels very warm to the touch.

I still doubt laptops based on those tech would be able to operate days on a pair of double A batteries. The entire laptop used under one watt including the display, hard to beat.

[NiHaoMike]

C2000™ 32-bit Real-time MCUs - 28x Fixed-point Series - TMS320F2809 - TI.com
It uses just under 0.1w at 10MHz. Two 2600mAh AA batteries have 6.5 Wh of power, enough to run the TMS320F2809 for over 2 and a half days even without additional power management. Then add an E-ink display, which only uses power when changing content.