A little earlier this week, AMD conducted its usual press briefing of the upcoming Radeon HD 7900 series, across various market regions. DonanimHaber scored and posted key slides from that presentation, with information that matters the most to enthusiasts.
To begin with, specifications. AMD's Radeon HD 7900 family will make use of a brand new high-performance GPU built on the 28 nm fabrication process, codenamed "Tahiti". This chip is said to pack no less than 4.3 billion transistors. With Tahiti, AMD makes its first big architecture change since Radeon HD 2000 series, a change from scalar VLIW-based computing GCN Quad SIMD, which is said to improve performance per mm2 die-area (a fascinating new way of measuring architecture efficiency).
Tahiti packs 2,048 stream processors, all of which are enabled on the Radeon HD 7970. These stream processors are arranged along 32 computing units, each holding 64 SPs. AMD gave Tahiti a wide memory bus. This chip has a 384-bit wide memory interface, which is said to dole out memory bandwidth upwards of 260 GB/s. It is populated with 3 GB of GDDR5 memory using twelve 2 Mbit memory chips. Radeon HD 7970 draws power from two PCIe power connectors, an 8-pin connector, and a 6-pin one.
AMD reference board design retains the black + red color scheme, and will use black colored PCB. The cooler shroud design is a bit more curvy, compared to the boxy HD 6900 board design. Display connectors include one each of DVI and HDMI; and two mini-DisplayPort connectors. All four connectors are confined to a single expansion slot area, leaving the second slot area dedicated to the cooler's hot-air vent. Board partners are required to include HDMI to DVI and active-DP dongles.
The cooler uses an aluminum channel design, to which heat is fed by a vapor chamber plate that draws heat from the GPU, memory chips, and VRM. The aluminum channels are then ventilated by a blower. AMD improved its blower design to have higher air-flow and better acoustics. Reference HD 7970 will feature dual-BIOS, much like reference HD 6900 series did. The two BIOS ROMs can be toggled using a small switch. The first BIOS ROM can be flashed, the second one is "locked', and packs a fail-safe reference BIOS.
Radeon HD 7970 will have a core clock speed of 925 MHz, which AMD claims can easily be overclocked to 1 GHz, "and beyond". We'll see about that.