Power

We regularly look at power consumption when talking about card performance, and for this review we want to look at two different aspects of power consumption. Since these cards all have potential for home theater systems given their HDCP compatibility, we want to look at not only power consumption during game performance, but also during BD video playback.

3D Acceleration Power Consumption

It's important to be aware of how much power your card draws when gaming so undue stress isn't put on your computer's power supply. Also, high wattage power supplies have bigger fans to keep them cool; that means a card with a lower power draw might be more desirable in a system that is built for as quiet operation as possible. To test the power load of these cards during 3D acceleration, we recorded the total wattage of the system with each of the cards installed while the system was idle for reference (i.e. no programs running), and then we recorded the total wattage of the system while running a few of the demos from 3DMark06. The 3DMark06 demos put stress on the GPU and we can then compare this to the idle wattage to get a general idea of how power hungry a card is.

Idle Power



Load Power



We can see that as you would expect, higher performance cards like the Sapphire Radeon X1950 XTX as well as the EVGA and BFG GeForce 7950 GX2 saw some of the biggest power draws. The reference NVIDIA 8800 GTX required a bigger power supply than the one we used for the other cards, so we put in a more powerful one with the necessary two PCIe connectors for that particular configuration. This will make these power numbers less consistent with the others, but we can still get an idea of how power-hungry these new cards from NVIDIA are. These cards are going to require higher watt power supplies to run, and so might not be the best choice for a quiet system. We noticed that the Albatron 7900 GS had a lower power draw than the others in its class, and the Gigabyte 7600 GS was the least power-hungry of all of these cards (as well as the least effective in video decoding).

Blu-Ray Playback Power Consumption

We also want to look at power consumption while playing back a BD movie with these cards. Because 3D acceleration takes more processing power than decoding video, we will expect to see a lower power draw in these tests, but as with CPU utilization, we will probably be seeing higher power draws with future Blu-Ray and HD-DVD content which will make use of higher bitrate encoding.

We took power reading in the same way as with CPU utilization: by playing back about a minute of video from our Blu-Ray movie "Click." We are also interested in seeing the kinds of power loads these cards have when hardware acceleration is disabled in order to see the contrast between power loads. Because cards of the same family (i.e. 7900 GS, 7950 GT, etc.) saw very similar power consumption without hardware acceleration enabled, we only recorded power in this state for one of each card family. These are the results of our tests.

Bluray Playback Power Consumption - No Hardware Acceleration


Bluray Playback Power Consumption - With Hardware Acceleration


Again we see that not surprisingly, the higher performance cards see greater power draws than lesser performing ones, but we don't see a big difference here between most of the cards. In many cases, higher clocked cards of the same type see a little higher power draws than their competitors, but in some cases (like with the Leadtek WinFast PX7900 GS TDH Extreme) we see lower power draws. This tells us that there will be variation in power draw between cards of the same type depending on what types of modifications the different vendors make to their cards. Again keep in mind that we used a different power supply for the NVIDIA GeForce 8800 GTX, so it's not really an apples-to-apples comparison.

In the future, we could see power consumption go down with acceleration enabled. As graphics hardware is better suited to processing video than a CPU, efficiency should go up when using hardware acceleration. At this point, there isn't much difference, but this could change when we move away from MPEG-2 and into higher bitrate content.

CPU Utilization Heat/Noise
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  • DerekWilson - Friday, November 17, 2006 - link

    We chose Click because of it's bitrate, not because or its artistic value :-)
  • msva124 - Thursday, November 16, 2006 - link

    quote:

    The fact that both the graphics card and display device must be HDCP capable, and most displays and graphics cards that people are currently using aren't HDCP compatible is a problem for consumers in general.
    Not really. The industry conforms to the the buyer, not the other way around.
  • Josh Venning - Thursday, November 16, 2006 - link

    Thanks for the comment, but the fact is that in the war against piracy, there is a lot of collateral damage.. Movie industries don't care if the consumer dislikes the fact that they have to upgrade their system in order to play the movie with the newest copy-protection standards. They only want to get rid of the pirates at whatever cost. This is why ultimately, everyone will have to conform.. or else not enjoy the benefits Bluray and HD DVD have to offer.
  • LoneWolf15 - Friday, November 17, 2006 - link

    quote:

    This is why ultimately, everyone will have to conform.. or else not enjoy the benefits Bluray and HD DVD have to offer.
    However, if people fail to adopt (or are extremely slow to adopt) HDCP and balk in enough quantity, the resulting drop in sales would likely force the content industry to rethink its position.

    Don't think that I believe this is going to happen; I believe most consumers are sheep, and they'll go out and buy what is needed. Some of them may even pitch a fit that they have to, but they'll still likely do it because they want the content more. If Jane and Joe consumers across the globe said "We won't buy it" though, I think things would change. They would have to, or the loss in sales would eventually drive the content industry out of business.

    Gives me a chance to remind myself that sometimes Sunshine/Outdoors 1.0 beats a home theater though, when the choice is available. :)
  • DerekWilson - Friday, November 17, 2006 - link

    But the industry is feeding the consumer the line that this is the only way it can be. The average consumer doesn't know or understand that things /could/ be done a different way.

    The average consumer doesn't realize what he or she is giving up by buying into the industry's FUD. Pirates don't rape artists of their money. The very studios the artists work get their first.

    It'd be great if everyone would boycott BD and HDDVD. But it's not going to happen.
  • LoneWolf15 - Monday, November 20, 2006 - link

    I agree, Derek.

    One thought...considering that this was an HDCP review, I'd enjoy seeing a followup that did some work with evaluating video playback quality. I game, but I want an all-round card solution. This explains why I got rid of my Geforce 6800 --good gaming card, video playback was average quality on supported accelerated formats, and nVidia's PureVideo (rev. 1, or should I say 0.99) fiasco drove me away from them.

    I'd be very interested to see how the current PureVideoHD and Avivo technologies square off, both in CPU usage under H.264, but also playback quality.

    And, while I know things could be done a different way, my pessimism towards the future is high. It explains why HDCP support was a requirement in purchasing an LCD panel this week. This really stinks, I'd have chosen standard-aspect over widescreen except for that (almost no 20" standard displays with HDCP; I say almost rather than none, but I didn't find any). I had to get a much bigger widescreen to make up for lack or vertical height relative to a standard-aspect display.
  • Sunrise089 - Thursday, November 16, 2006 - link

    Not always - see the record industry for the ideal example of those that do not conform to anything other than their own outdated models.

    I'm an enthusiastic capitalist, but some industries or industry groups have been unable or unwilling to adapt to the rapid pace of technology driven change in the internet era. Such groups have oftentimes fallen back upon legal attempts to force the marketplace into accepting their idea of how buisness should be done. The RIAA and the companies it represents refused to understand the oppurtunities the internet created for them, AND they refused to offer the product the consumers desired, because it didn't fit their model. The iTunes success story has forced them to sit up and take notice, and now rather than try to finally offer what customers want, they continue to wish to put the genie back in the bottle, and try to offer digital content to consumers only when it can be made 'safe' through DRM. DRM is NOT a market driven movement, it's a movement that attempts to remove one of the central features of the internet era - increased ability to steal content. Well fine, but the studios must think they exist in a vacuum because all they want to talk about is that negitive, not the positive factor of FAR lower distribution cost, and zero physical production cost. So we have all this focus on piracy protection, at huge cost to the end-user, that has essentially reduced the product purchased from a copy of the original work, down to a semi-permanant pay-per-view license, but the cost of the 'product' has remained the same.

    Tell me where the market forces are here?
  • DerekWilson - Friday, November 17, 2006 - link

    The market forces are neatly tied up and tossed out with the garbage thanks to the VERY anti-consumer DMCA (digital millennium copyright act).

    We can hardly even ask for what we want without being shot down by the DMCA.

    Sure, we still have "fair use" rights. But the problem is that we can't touch the content to which we supposedly have fair use due to the legal protection afforded encrypted content by the DMCA.

    If we were given unprotected movies, it would still be illegal to copy and distribute this content. It's almost like car manufacturers making cars that could only be driven by one person: it's still illegal to steal a car, but now the owner is restricted in his legal uses for the car. The comparison is even more accurate if there were laws in place to keep the owner of a car from circumventing the restriction to allow another person to drive it.

    The only thing that DRM does is keep us from the myriad legal uses we could have for our movies (and music for that matter) that don't fall under just watching and listenting. Or didn't you know you had any right to use that content in other ways?

    We couldn't even show you screen shots of the movie to compare image quality -- screen capture must be disabled during video playback.

    Sorry for the rant -- this stuff just really bugs me.
  • mino - Wednesday, November 22, 2006 - link

    Well, me not.

    Before , at college I didn't buy a single DVD cause I have no money to spend on unnecessary stuff.

    Now I buys some DVD here and there.
    But hell!
    To ask equivalent of $30 for a DVD in a country where average daily wage is $25!!!

    Also, to send some ***hole from RIAA analogue to saturday local middle school kids performance to have them pay $200 for singing some 30yrs old forgotten song on public area!!!
    Are they crazy? [Yes, they are.]

    I rememmber the co-called "totalitarian" communism jet.
    And I can say, in that era people had far more liberties than they have in US now.

    Sure, one can have a gun now. But he can't even sing or use some frickin publicly known math algorithm someone pattented. WTF?
    Lets' patent the wheel!

    20yrs ago we could not critisize the government here. But pretty much anything other than that was allowed(legal). From owning (registered)guns to singing whatever your mouth was capable off.

    Now we are gonna have all of the wondelfull liberties ... or, better said, the corporations are gonna have all the wondelfull liberties.


    To topic: what happens if you use analog output? You mentioned that the playback software asked for analog output when non-HDCP card was found...
  • AGAC - Thursday, November 16, 2006 - link

    I thought I was going to read an article to help me choose what hardware should I have if I wanted to playback some HDCP media.

    Gaming benchmarks? Great! So now I know that a Geforce 8800 GTX is faster then a Radeon X1600! Thanks a lot.

    What about OS settings, WinXp and Linux compatibility (is BluRay for Vista only?), monitor options, which card supports video in, why monitor manufacturers don´t advertise their HDCP compliant displays? Should I buy a desktop monitor? Should I buy an HDTV? what about all of it? So many questions...

    I read it all and still don´t have a clue.

    Sorry for the rant, guys. It´s this HDCP joke they´re playing on us all. Blockbuster video nearby has HD-DVD and BR titles and I laugh at the shelf because I want to play those in my pc and don´t know how to do it. I don´t remember having so much trouble with computer media since the days with my MSX computer and it´s cassete tapes back in early 80´s.

    Regards from Brazil.

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