AMD has officially announced its first ever 28nm-based graphics card: the Radeon HD 7970. The first member of the 'Southern Islands' GPU family is based on the 'Tahiti' core and utilizes a fresh architecture AMD refers to as "Graphics Core Next." The latter introduces a non-VLIW SIMD engine and is claimed to deliver a big improvement in performance per square millimeter of GPU space over the prior generation.

Update: TechSpot's review of the Radeon HD 7970 is now live.

Spec-wise, the Radeon HD 7970 packs 2048 Stream Processors, 128 Texture Units, 32 ROPs, a core clock of 925 MHz, a 384-bit memory interface, and 3 GB of GDDR5 memory clocked at 5500 MHz. It has the highest transistor count of any GPU yet at 4.31 billion and offers massive improvements over the previous single-GPU flagship – 3.79TFLOPs of theoretical computing performance compared to 2.7TFLOPs for the Radeon HD 6970, and 264GB/sec of memory bandwidth over the 176GB/sec of the 6970.

Cards in the 7900 series can make full use of the newest and speediest PCI Express (PCIe) 3.0 x16 bus interface, though they will retain backwards compatibility with both 1.0 and 2.0 standards.

Other enhancements include PowerTune and AMD ZeroCore Power technologies, which allow for higher performance levels while maximizing power efficiencies, App Acceleration to improve HD video playback and general performance, and an update to AMD's Eyefinity technology that brings new monitor configurations (up to 5-by-1 landscape and portrait with  2560 x 1600 monitors), flexible bezel compensation, stereoscopic 3D support across three displays and support for up to five independent audio streams.

AnandTech tested AMD's newest card and summarizes its gaming performance and power usage like this: "Depending on the game being tested it's anywhere between 5% and 35% faster than NVIDIA's GeForce GTX 580, averaging 15% to 25% depending on the specific resolution in use. Furthermore thanks to TSMC's 28nm process power usage is upwards of 50W lower than the GTX 580, but it's still higher than the 6970 it replaces."

The reference AMD Radeon HD 7970 card features a dual-slot cooler which uses vapor chamber technology, has CrossFireX support, and includes four display outputs: one dual-link DVI, one HDMI 1.4a and two mini DisplayPort 1.2. It'll arrive in January 9 just ahead of CES with a price tag of $549.