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Energy Efficient Graphics Processors?
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?"
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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Theoretically, the more physical cooling you can give a chip, the more energy it can suck up (i.e. the more heat it can disipate). If anything, having less room for cooling should force energy efficiency (so that they don't have to disipate as much heat).
The Opteron "HE" is classed at 55 watts (I suppose that is at 2.0 GHz or so)
The P4 extremely expensive edition dissipates 103 watts at 3.4 GHz.
So in comparison to other desktop processors it does fairly well. Now there are efficient G4 class processors coming from Motorola the MPC7447 is said to dissipate 10 watts at 1 GHz.
I am not comparing any of these processors GHz to GHz because we all know that is not an accurate method of comparison. But I think it wrong to classify the MPC7447 as a desktop processor or even a processor for a desktop replacement type laptop. But then again maybe it's because after using OS X on a G5 I'll never take Motorola seriously (for the desktop) again. That's not saying Motorola is a bad company or their chips are bad! I develop almost exclusively on them at work, but then again I am an embedded developer.
Nothing in the world is more dangerous than sincere ignorance and conscientious stupidity.
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.