The AMD Radeon HD 7970 specifications are listed in the following table in comparison with the AMD Radeon HD 6970.
We’ve got a reference sample of the new AMD card without any packaging or accessories. Compared to the HD 6970, the HD 7970 looks more attractive with its glossy black cooler casing with a red insert and pressed-out letters “Radeon”.
This casing isn’t very practical as you can’t help leaving greasy fingerprints on it, but it does look splendid. The size hasn’t changed much since the previous flagship. The Radeon HD 7970 3GB measures 278 x 100 x 38 millimeters.
The new card has been deprived of one DVI output, but its vent grid has expanded thanks to that.
So, the connectors include one dual-link DVI-I, one HDMI version 1.4a, and two DisplayPorts version 1.2. Off-the-shelf versions of the card will come with an HDMI->DVI adaptor for connecting two monitors with DVI inputs simultaneously. Coupled with a special MST hub (to be released by summer 2012), the two DisplayPorts will enable Multi-Stream technology to support up to six monitors concurrently.
There’s nothing new about power connectors, MIO interface and dual BIOS. The Radeon HD 7970 features one 8-pin and one 6-pin power connector, two connectors for building CrossFireX configurations, and a small switch for choosing the BIOS to use.
Notwithstanding the 28nm tech process, the new card has not become more economical than its predecessor. The peak power draw is declared to be 250 watts in 3D applications. However, the Radeon HD 7970 is able to lower its 2D power draw down to 3 watts (when the monitor is turned off), something that the Radeon HD 6970 couldn’t do. If you've got a CrossFireX configuration, all graphics cards, save for the primary one, can be turned off upon leaving 3D mode, which should have a positive effect on the power consumption, noise and temperature of such rigs. We will surely check this out in our upcoming reviews of off-the-shelf Radeon HD 7970s.
The PCB and component layout do not seem to have changed much since the previous flagship.
But we can note a few differences. First of all, the reference Radeon HD 7970 features 5+1 power circuit design with 6 phases for the GPU and 1 phase for the graphics memory. The power system is managed by a CHiL CHL8228G controller.
High-quality DirectFETs can be spotted on the PCB. We’ve seen them before on MSI’s graphics cards. They are superior to the Radeon HD 6970’s Volterra components in electrical resistance, inductance and heat dissipation. These chips can give their heat away both to the heatsink and to the PCB.
The GPU has a metallic frame that protects not only the corners and edges of its wafer but also the area immediately around the die.
The die is positioned at 45 degrees and lacks any marking. The latter can be read from the frame. We've discussed the GPU configuration in the previous section. Here’s the info in brief: 2048 unified shader processors, 32 raster operators, and 128 texture-mapping units. The clock rate is 925 MHz at 1.17 volts in 3D mode and 300 MHz at 0.95 volts in 2D mode.
The card's 3 gigabytes of GDDR5 memory are represented by 12 FCFBGA chips located on the face side of the PCB. Labeled H5GQ2H24MFR R0C, the chips are manufactured by Hynix Semiconductor.
They have a clock rate of 5500 MHz, just like on the Radeon HD 6970, but the memory bus is expanded from 256 to 384 bits, increasing the memory bandwidth from 176 to 264 GB/s. The memory clock rate is lowered to 600 MHz in 2D applications.
Here is a summary of the reference AMD Radeon HD 7970 specs:
We’ve used GPU-Z to read the card’s BIOS.