In the final part of our review, we look into the overclocking abilities of the 28nm 'Tahiti XT' GPU, run extensive but relevant performance tests, and give an objective conclusion of the AMD Radeon HD 7970.

Overclocking

The overclocking potential of the Radeon HD 7970 has been much vaunted in the recent leaks and it certainly didn't disappoint. Even without any software or hardware voltage mods, we managed to bring the CPU core from the default 925MHz up to the maximum 1125MHz that CCC would allow. We also turned memory up to 1500MHz and Power Control to +20% to prevent throttling. 

 

Testing with FurMark – with the fan left at auto, it was still spinning silently and temperatures maxed out at a comfortable 86 degrees celcius

 

The updated GPU-Z 0.5.7 allows you to read card information off the 7970's SMBIOS

 

Every increment on the way, we went the extra mile to ensure that there was actually scaling (and not bs throttling). With clocks like these on stock voltages and cooling, you'll wonder how much higher it can go when software or hardware voltage modifications together with better cooling are applied to this card. Looks like the 28nm process die shrink did pay off…

 

 

Check also 

Part 1: A Look at Graphics Core Next (GCN) Architecture

Part 2: The Card Design (Hardware Components and Cooling)