5 - New Power Consumption Features

Power Consumption

Since we just briefly touched the topic of power consumption, for a product of this caliber it's really not that bad. More transistors means more power consumption ... well you figured that out yourself already I guess. The new GPU however is one of the most energy aware products you'll find on the market today. NVIDIA made sure several new power states are active in the GPU. What this means is that depending on the task at hand you assign to the GPU, it'll react to that in terms of power consumption. NVIDIA's integrated these 'p-states' and allows the GPU to alter clocks, voltages and frequencies on the fly. Very interesting is that certain parts of the GPU when not used, can be shut down, preserving energy. In GPU terminology this is called clock-gating circuitry, it effectively "shuts down" blocks of the GPU which are not being used at a particular time, reducing power during periods of non-peak GPU utilization.

I've been trying to figure out a way to actually show these dynamic processes and I can actually show you a little tip of that iceberg.

Above in the screenshot you can for example see the core domain hop from 400 towards 600 MHz when needed. But more interestingly, have a look at the shader domain, it's clocked down towards 100 MHz if not used. Once we fire of a 3D application at it it'll jump up towards it's designated clocks, and the same thing happens for the memory.

For example .. in idle this 1.4 Billion transistor encounting graphics processor only consumes 25 watts ... I mean come on, that is just nothing. I think the previous generation products consumed up-to 70 watts alone in idle. Another nice example is that movie playback is accelerated and enhanced over the GPU (Purevideo), when you decode 1080P content (Blu-ray) movies you'd figure that it would use up a lot of power, right ? Think again. Remember what I said about the GPU being able to shutdown segments of the GPU? Likely (and I'm not 100% sure here) mainly the video processor, IO and perhaps one shader block for some post-processing are at work. While decoding a 1080P movie over the GPU this product utilizes only 35 Watts. That's pretty amazing to be honest. Let's take an overview on what we just said:

• Idle/2D power mode: approx. 25W
• Blu-ray DVD playback mode: approx. 35W
• Full 3D performance mode: varies - worst case TDP 236W for GTX 280
• Full 3D performance mode: varies - worst case TDP 182W for GTX 260
• HybridPower mode: effectively 0W

Using a HybridPower-capable nForce motherboard a GeForce GTX 200 GPU can be fully powered off when not performing intensive graphics operations and graphics output can be handled by the motherboard's IGP.

So though the processor can peak towards 225-235 Watt with hefty gaming, the reality is that it's just as much as a GeForce 8800 Ultra, yet you have double the performance and the overall picture of this GPU in more common situations seems to be very energy efficient.

The GeForce GTX 280 requires you to connect both a 6-pin and 8-pin power connector.