Infrared thermographyFor this test we used the new protocol described here.
First of all, here's a summary of all the readings:
The difference between the Radeon HD 7900s at idle is almost nothing.
In load, while the Radeon HD 7970 GHz’s higher energy consumption results in higher noise levels, it doesn’t have any impact on the internal temperatures as most of the hot air is expelled from the casing.
Finally, here’s what the thermal imaging shows:
Strangely, in spite of the additional Watts, the Radeon HD 7970 GHz Edition’s power stage doesn’t heat up any more than on the standard card. As the components and cooling system are identical, it's possible that the increase in the flow of air compensates for the additional heat.