Temperatures in idle are great, but under load temperatures are just ok.
|GPU Temperature Comparison|
|AMD HD 7970 GHz Edition||40°C||83°C|
|VTX3D HD 7970 X-Edition||39°C||75°C|
|MSI HD 7970 Lightning||39°C||76°C|
|AMD HD 7970||45°C||78°C|
Important: GPU temperature will vary depending on clocks, voltage,
cooler design and production variances. This table just serves to provide
a list of typical temperatures for similar cards, reached during TPU review.
Clock ProfilesModern graphics cards have several clock profiles that are selected to balance power draw and performance requirements.
The following table lists the clock settings for important performance scenarios and the GPU voltage that we measured. We measure on the pins of a coil or capacitor near the GPU voltage regulator.
|GPU Voltage |
|Desktop||300 MHz||150 MHz||0.95 V|
|Multi-Monitor||500 MHz||1500 MHz||0.95 V|
|Blu-ray Playback||500 MHz||1500 MHz||0.95 V|
|3D Load||1050 MHz||1500 MHz||1.20 V|
|CCC Overdrive Limits|
PowerTune BoostIn their press briefing AMD talked about how they improved PowerTune by adding a boost clock mechanism, which provides higher clocks and better performance.
For the graph below, we recorded all GPU clock, GPU voltage combinations of our benchmarking suite for the 1920x1200 resolution. The plotted points have transparency, so they can add up to indicate more often used values. A light color means the clock/voltage combination is rarely used, a dark color means it's active a lot.
If you've seen our NVIDIA Kepler reviews, you'll remember that this graph shows a diagonally rising pattern on those cards. On AMD's card we see only a total of four clock and voltage combinations being available.
AMD's mechanism is really basic, in high-performance 3D, the card runs at a single fixed clock speed of 1050 MHz, just like any other AMD card did in the past. Only when AMD's PowerTune algorithm detects an overload situation, it will reduce the clock speed to a fixed value of 1000 MHz, that's it.
Each of these two clocks (1050 MHz and 1000 MHz) has one voltage associated with it. You can see two additional faint points at the other clock's voltage, but these are measurement artifacts from the switching of clock and voltage, which does not happen at the same time. For example, when going to 1000 MHz to 1050 MHz, the voltage will also change to 1.219 V from 1.163 V. But since either the clock change or the voltage change will be finished first, it will create a "new" combination of clock and voltage, which is displayed in the plot.