Another leaked slide unveils some of the power management enhancements NVIDIA made to the new GeForce GTX 200 GPU series. The slide says there are four different performance/power modes employed:
Idle/2D power mode: approx. 25W
Blu-ray DVD playback mode: approx. 35W
Full 3D performance mode: varies - worst case TDP 236W
HybridPower mode: effectively 0W
Using a HybridPower-capable nForce motherboard, such as those based on nForce 780a or 790i chipsets, 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.
For 3D graphics-intensive applications, the NVIDIA driver can seamlessly switch between the power modes based on utilization of the GPU. Each of the new GeForce GTX 200 GPUs integrated utilization monitors ("digital watchdogs") that constantly check the amount of traffic occuring inside of the GPU. Based on the level of utilization reported by these monitors, the GPU driver can dynamically set the appropriate performance mode (i.e., a defined clock and voltage level) that minimizes the power draw of the graphics card - all fully transparent to the end user.
The GPU also has clock-gating circuity, which effectively "shuts down" blocks of the GPU which are not being used at a particular time (where time is measured in milliseconds), further reducing power during periods of non-peak GPU utilization.
All this enables GeForce GTX 200 graphics cards to deliver idle power that is nearly 1/10th of the maximum power (approx 25W on GeForce GTX 280 GPUs).
Use Disqus to post new comments, the old comments are listed below.
Re: NVIDIA GeForce GTX 280 power enhancements detailed by Anonymous on Monday, June 09 2008 @ 14:03:04 CEST
Since we aren't going to see a 55nm mobile variant of the GT200 for a year, I'm thinking this is a bunch of marketing bull...
What user is going to buy a top end GPU and NOT do 3D? They certainly don't seem to be using tons less power in 3D mode, that's for sure.