Like the reference design, the XFX R7970 uses a vapor chamber to cool the core. The aluminium finned array is sandwiched between the copper baseplate and the twin fans which draw air in from outside, through the heatsink and out of the GPU with the majority of hot air passing outside thanks to the longitudinal fins.
Contact with the core was excellent so there would be no need to replace the TIM which is all very good and well because doing so would mean breaking the warranty seals on the screws, voiding the warranty. The memory and VRM have sticky thermal interface tape to transmit heat and are placed on an aluminium mid-plate.
The R7970 is very much a reference design having the VRM area closet to the PCIe power sockets. There are 12 256MB memory modules surrounding the main core, itself having a parial IHS.
The HD7970 is a 5+1+1 phase design and uses Coiltronics ferrite core lo profile surface mount inductors (1007R3-R15), these along with an abundance of solid capacitors should ensure a smooth, stable power delivery - perfect for overclocking.
The VRM discussed above is managed by the CHiL 8228G controller. This little device furnishes us with overclocking options allowing voltage and frequency changes. AMD have been there usual cautious selves though so for this review we will be going that extra mile to see just how far these cards can go.
The memory chips hail from HYNIX with a product code of H5GQ2H24MFR R0C which is rated at 6GBps at 1.6v. Already clocked at 5200MHz we hope to improve on this.
Finally, we reach the beating heart of the XFX R7970 Black Edition - the Tahiti core. 28nm along with GCN architecture, the flagship AMD core has impressed us so far, not least because of it's overclocking ability. This time around, the core is arrives pre-overclocked to 1GHz and so the overclocking headroom is usually diminished slightly however, as we will see later, this isn't always the case...