Putting realistic, repeatable load on a GPU to get a decent idea of its real world power consumption and thermal output has long been something we've experimented here at bit-tech. We've found that synthetic benchmarks such as FurMark thrash the GPU constantly, which simply isn't reflective of how GPU will be used when gaming.
It's such a hardcore test that any GPU under test is almost guaranteed to hit its thermal limit, the mark at which the card's firmware will kick in, speeding up the fan to keep the GPU within safe temperature limits. Conversely, simply leaving a game like Crysis running at a certain point also isn't reflective of real world use. There's no guarantee that the GPU is being pushed as hard as other titles might do, and the load will vary from play through to play through.
Eventually then, we've decided to use 3DMark06's Canyon Flight test as a real world representative, repeatable graphics test. It's a ferociously demanding test, pushing graphics cards to their limit, but also containing peaks and troughs in performance that match real world game play.
As the test is so demanding and GPU limited, we've set 3DMark to run the test at 1,280 x 1,024 with 0xAA and 16xAF (enabled in the driver), constantly looping the test for thirty minutes and recording the maximum power consumption and GPU Delta T (the difference between the temperature of the GPU and the ambient temperature in our labs).
Power Consumption (idle)
Windows 7 Desktop (Aero enabled) Idle Power Usage
Nvidia GeForce GTX 295 1,792MB
ATI Radeon HD 5970 2GB
Nvidia GeForce GTX 480 1,536MB
Nvidia GeForce GTX 470 1,280MB
Nvidia GeForce GTX 285 1GB
ATI Radeon HD 5870 1GB
ATI Radeon HD 5850 1GB
186
168
164
160
147
145
142
0
50
100
150
200
Watts at socket
Power Consumption (load)
3DMark06 Canyon Flight test, 1,280 x 1,024 0xAA 16xAF, Peak Temperature
Nvidia GeForce GTX 295 1,792MB
Nvidia GeForce GTX 480 1,536MB
ATI Radeon HD 5970 2GB
Nvidia GeForce GTX 470 1,280MB
Nvidia GeForce GTX 285 1GB
ATI Radeon HD 5870 1GB
ATI Radeon HD 5850 1GB
382
376
352
341
305
276
237
0
100
200
300
400
Watts at socket
Thermal Performance
Heat (idle)
Windows 7 Desktop (Aero Enabled)
ATI Radeon HD 5970 2GB
Nvidia GeForce GTX 470 1,280MB
Nvidia GeForce GTX 295 1,792MB
Nvidia GeForce GTX 480 1,536MB
ATI Radeon HD 5870 1GB
Nvidia GeForce GTX 285 1GB
ATI Radeon HD 5850 1GB
26
25
21
20
19
19
15
0
5
10
15
20
25
Delta T in °C
Heat (peak)
3DMark06 Canyon Flight test, 1,280 x 1,024 0xAA 16xAF, Peak Temperature