Power and Power Management

Power is a major concern of many tech companies going forward, and just adding features "because we can" isn't the modus operandi anymore. Now it's cool (pardon the pun) to focus on power management, performance per watt, and similar metrics. To that end, NVIDIA has beat their GT200 into such submission that it's 2D power consumption can reach as low as 25W. As we will show below, this can have a very positive impact on idle power for a very powerful bit of hardware.

These enhancements aren't breakthorugh technologies: NVIDIA is just using clock gating and dynamic voltage and clock speed adjustment to achieve these savings. There is hardware on the GPU to monitor utilization and automatically set the clock speeds to different performance modes (either off for hybrid power, 2D/idle, HD video, or 3D/performance). Mode changes can be done on the millisecond level. This is very similar to what AMD has already implemented.

With increasing transistor count and huge GPU sizes with lots of memory, power isn't something that can stay low all the time. Eventually the hardware will actually have to do something and then voltages will rise, clock speed will increase, and power will be converted into dissapated heat and frames per second. And it is hard to say what is more impressive, the power saving features at idle, or the power draw at load.

There is an in between stage for HD video playback that runs at about 32W, and it is good to see some attention payed to this issue specifically. This bodes well for mobile chips based off of the GT200 design, but in the desktop this isn't as mission critical. Yes reducing power (and thus what I have to pay my power company) is a good thing, but plugging a card like this into your computer is like driving an exotic car: if you want the experience you've got to pay for the gas.

Idle Power 

Idle power so low is definitely nice to see. Having high end cards idle near midrange solutions from previous generations is a step in the right direction.

Load Power 

But as soon as we open up the throttle, that power miser is out the door and joules start flooding in by the bucket.

Cooling NVIDIA's hottest card isn't easy and you can definitely hear the beast moving air.  At idle, the GPU is as quiet as any other high-end NVIDIA GPU.  Under load, as the GTX 280 heats up the fan spins faster and moves much more air, which quickly becomes audible. It's not GeForce FX annoying, but it's not as quiet as other high-end NVIDIA GPUs; then again, there are 1.4 billion transistors switching in there.  If you have a silent PC, the GTX 280 will definitely un-silence it and put out enough heat to make the rest of your fans work harder.  If you're used to a GeForce 8800 GTX, GTS or GT, the noise will bother you.  The problem is that returning to idle from gaming for a couple of hours results in a fan that doesn't want to spin down as low as when you first turned your machine on.  

While it's impressive that NVIDIA built this chip on a 65nm process, it desperately needs to move to 55nm.

GT200 vs. G80: A Clock for Clock Comparison The Test
POST A COMMENT

108 Comments

View All Comments

  • woofermazing - Tuesday, June 17, 2008 - link

    Isn't the R700 high-end model going to have a direct link between the two cores. Could be a false rumor, but i would think that would solve a lot of problems with having two GPU's on a single board, since games would see it as 1 chip instead of a Crossfire/SLI setup. And besides, why the heck does it matter what the card looks like under the cooler. If it delivers better performance than Nvidia's offering without driver headaches, I don't think most gamers are going to care. Reply
  • VooDooAddict - Tuesday, June 17, 2008 - link

    Why am I the only one happy about this product?

    Since the release of the 8800GTX top end single GPU performance has been a little stagnant... then came the refresh (8800GT/8800GTS-512) better prices came into effect.

    Now we've got the new generation, and like in years prior, the new gen single GPU card has near performance of the previous gen in SLI. Price is also similar with when NVIDIA launched the first 8800GTX.

    Sure, I wish they came in at a lower price point and at less power draw. (Same complaints that we had with the original 8800GTX). Lower power and lower price will come with a refresh.

    Will I be getting one? ... nahh these cheap 9600GTs, overclocked 8800GT's and 8800GTSs will be the cards I recomend till i see the refresh. But I'm still happy there's progress.

    I'm hoping the refresh hits around the same time as Intel's updated quad core.
    Reply
  • DerekWilson - Tuesday, June 17, 2008 - link

    i think its neat and has very interesting technology under the hood.

    but i'm not gonna spend that much money for something that doesn't deliver enough value (or even performance) compared to other solutions that are available. you pretty much reflect my own sentiment there: it's another step forward but not one that you're gonna buy.

    i think people "don't like it" because of that though. it just isn't worth it right now and that's certainly valid.
    Reply
  • greenx - Tuesday, June 17, 2008 - link

    There are two ways I can look at this article.

    1)First an foremost at the heart of a real gamer ticks the need for good story lines fed by characters you will never forget, held by a gameplay you will fall in love with and finally covered by graphics that will transport you to another world (kinda like when I first played FF VII on my PC).

    Within the context of the world we live in today I wonder what is really going through the minds of these people selling $600+ video cards. Kinda like those $10 000+ PCs. Madness. Sure they have their market up there but I shudder to think of how much money has been poured into appeasing a select few. Furthermore for what reason? Glory? I don't know but seeing as how the average gamer is what has made the PC/Gaming scene what it is, where does a $600+ video card fit into the grand scheme of things?

    2) The possibilities that these new cards open up certainly seem exciting. The comparison with intel has been justified, but considering the other alternatives out there are much further ahead in development, who is going to bypass intel/amd/etc for a GPU technology based supercomputer?
    Reply
  • DerekWilson - Tuesday, June 17, 2008 - link

    two address point 2):

    developers will bypass Intel, AMD, SUN, whoever owns Cray these days, and all other HPC developers when a technology comes along that can speed up their applications by two orders of magnitude immediately on hardware that costs thousands (and in large cases millions) less to build, run and develop for.
    Reply
  • evolucion8 - Tuesday, June 17, 2008 - link

    LOL that was quite funny but incorrect as well, there's more than 4 Billion of people in China, in the future probably nVidia will launch a 4 Billion Transistors GPU hehe. It will require a Nuclear Reactor to turn it on, a and two of them to play games :D Reply
  • 7Enigma - Wednesday, June 18, 2008 - link

    4 Billion? Did you just make that out of thin air. Latest tabs show approximately 1.4 billion (give or take a couple hundred million). The world population is only estimated at 6.6 billion, so unless 60% of the people in the world are living in China, you're clueless.

    http://geography.about.com/od/populationgeography/...">http://geography.about.com/od/populationgeography/...
    Reply
  • Bahadir - Tuesday, June 17, 2008 - link

    Firstly I must say I enjoyed reading the whole article written by Anand Lal Shimpi & Derek Wilson. However, what does not make sense to me is the fact that "At most, 105 NVIDIA GT200 die can be produced on a single 300mm 65nm wafer from TSMC", but by looking at the wafer, only 95 full dies can be seen. Is this the wrong die?

    Also, it is not fair to compare the die of the Penryn against the GTX 280die because Penryn's die was made in 45nm process and GTX280 was made in 65nm die. Maybe it would be fair to compare it with the Conroe (65nm) die. But well done folks for putting an excellent article together!
    Reply
  • Anand Lal Shimpi - Tuesday, June 17, 2008 - link

    Thanks for your kind words btw :) Both of us really appreciate it - same to everyone else in this thread, thanks for making a ridiculously long couple of weeks (and a VERY long night) worth it :)

    -A
    Reply
  • Anand Lal Shimpi - Tuesday, June 17, 2008 - link

    You're right, there's actually a maximum of 94 usable die per wafer :)

    Take care,
    Anand
    Reply

Log in

Don't have an account? Sign up now