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Energy Efficient Graphics Processors?

Posted by Cliff on from the GPU's-that-are-kind-on-your-electric-bill dept.

An anonymous reader asks: "The trends for graphics hardware these days seems to be to draw more power and create more heat to get faster processors and push more polygons. Yet in the CPU arena chips like the Via C3 and Epia, Transmeta Crusoe and Astro, Intel Pentium M, and IBM/Motorola PowerPC (G3-5) seem to favor more power per megahertz and cooler runnings without significant performance loss. Is this just because of the nature of the CPU versus GPU? I understand a GPU die is almost entirely reserved for calculation while the CPU is only 20% of so for calculation. Or are the graphics chip makers merely refusing to innovate and take routes that would reign in out of control energy consumption because of the race for more polygons? What kind of architectural changes could be implemented to alleviate graphics card power gluttony?"

9 of 60 comments (clear)

  1. Unfair comparison by complete+loony · · Score: 4, Interesting

    The latest Pentiums are power hungry hogs too, if you want the latest and greatest it's going to be less effienct than it could be. Low power consumption, size of heat sinks, volume of fans are less of a design constraint that the raw power of the chip.

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  2. Heatsinks for GPUs by Jmechy · · Score: 2, Interesting

    Sure, we can put a full foot of copper on our CPU's, but everybody screams and moans when Nvidia builds a cooler that takes up the adjoining PCI slot. Graphics cards are limited with the space they can take up for their cooling solutions, and they certainly pay for that in heat generation.

    1. Re:Heatsinks for GPUs by Myself · · Score: 4, Interesting

      One of the problems is that PCI and AGP boards are "upside down" compared to ISA boards. Think component-side versus solder-side. In the case of ISA and PCI boards, it's important not to exceed a certain width because of adjacent slots, but since the AGP slot is always the first one, an AGP board could extend pretty far in the other direction.

      Why don't they simply mount the GPU to the other side of the board to allow a much larger heatsink? I think this is either a design tradition or a limitation of the pick-and-place assembly machines, because there's no technical reason not to. I suppose if taken to an extreme, it could lead to physical fit problems in certain cases, but let's not go that far.

    2. Re:Heatsinks for GPUs by shepd · · Score: 2, Interesting

      >Why don't they simply mount the GPU to the other side of the board to allow a much larger heatsink?

      Filter capacitors. I've often found them mounted just behind the video card. A combination of a heatsink on the wrong side, along with these, would be a big problem, even if they didn't touch (most capacitors don't appreciate heat).

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      If you could be told what you can see or read, then it follows that you could be told what to say or think - BoC
  3. GFFX 5200 by Hythlodaeus · · Score: 3, Interesting

    Most versions of the Geforce FX 5200 (non-Ultra) run fanless, which should speak to its relative energy efficiency. It also runs about as fast as a Geforce 3, unfortunately.

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  4. You've already answered your own question by photon317 · · Score: 3, Interesting


    You've compared high-end 3d desktop gamer cards which are excessive on heat and power to CPU chips which are designed for lower power low heat situations. The difference isn't nearly as pronounced with a more valid comparison on the CPU side, say a high end P4EE or Athlon64/Opteron. Also as you've stated, the GPUs are almost entirely dedicated to high-power processing, whereas the CPUs spend a lot of their silicon on other things. A high end GPU is generally superior to a high end CPU in terms of raw computing power. Therefore, it needs more power and makes more heat. If you forced intel or amd to build a CPU for you right now that had the raw compute potential of the latest high end cards, they'd have a hard time doing so without being just as hot and power hungry. All these things scale over time, but the demands of the user and his software scale up to meet it as well.

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  5. Display Quality Too by turgid · · Score: 3, Interesting
    I'm still using my TNT2 Ultra which I bought in the Xmas sales in 1999 in my Athlon. The display qulaity is superb, but it's really long in the tooth. I bought it for playing Quake 3 on Linux (I don't have Windows) and nowadays I don't do much gaming, but I'd like to upgrade and migrate this excellent card into one of my old machines.

    I tried a no-name GeForce 4 MX440 a couple of years back, but the display quality was awful. It was so poor I had to downgrade to 1280x1024 on my 19" Trinitron screen. After a few months the card broke and I went back to my TNT2 Ultra (Creative Labs) and back up to 1600x1200.

    I was thinking about getting something fanless and by nVidia since their (binary-only) drivers are superb on Linux (I don't do the idealogical zealotry as much nowadays).

    High-performance 3D is nice when you need it, but nowadays stuff is so powerful for under $100 that there's not much point to buying something really expensive. Some of us want a crisp, high-resolution display, flicker-free (70Hz+) without a great big noisy fan.

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    Stick Men
    1. Re:Display Quality Too by Naffer · · Score: 2, Interesting

      My Nvidia 5900 ultra bit the dust early last year I was forced to pull out my old Creative Labs PCI TNT2. I run a 21" CRT at 1600x1200x85 and the display was SO bad with the TNT2 that I had to drop it to 1024x768x85 before the screen was really usable. Older cards just really often don't have the RAMDACs to keep up with nice monitors.
      By the way, if you want crisp flicker free 2d, then why not just get a Matrox card? Nvidia and ATI are catering to a specific market so a 2d Matrox card might just suit your needs better.

  6. Re:G5? by MarcQuadra · · Score: 2, Interesting

    The G5 is VERY efficient, using about half the juice of a similarly-powered P4. The problem is in perception, it's a lot hotter than any PREVIOUS Apple CPU offering and Apple case design tends to aim for more heatsink and bigger fans than small loud HSF combos. This leads to the idea that the G5 is a monster power draw when it is quite benign.

    It's just like when Mac users complained about the 'hot' G4 PowerBook, it wasn't much different than high-end P4 laptops of it's day, but Mac users expected cooler machines, so they raised a stink about them.

    My Athlon draws much more juice at 1.8GHz than a PPC970 at 2GHz, and the 970 can mop the floor with any Athlon-XP.

    The G4 74xx and 75xx are also quite good in power draw, but the design is old enough that it really can't run much over 1.5GHz, remember that the core of that chip (PPC750) was 233MHz when it came out; the Altivec implementation and onboard cache, while nice, are huge real-estate hogs on the die.

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    "Sometimes, I think Trent just needs a cup of hot chocolate and a blankie." -Tori Amos on Nine Inch Nails