Radeon HD 6990 Review Introduction
It is quite understandable that AMD and NVIDIA slog it out in key price segments under $500, at price points wheregraphics card as a component competes in the market with gaming consoles. Almost every household has a PC with a PCI-Express slot these days, and consumers opt for a simple hardware upgrade by buying that graphics card to turn their MS Excel boxes into Games for Windows PCs. What happens at price points above $500? Pitched battles between the two GPU vendors for paper supremacy, even when no graphics card in the upper price points can really make volumes. For GPU vendors, having the fastest graphics card, like the Radeon HD 6990 in the market has two distinct advantages: the PR weapon of "we make the fastest in the market", and being able to capture the high-end PC and enthusiast markets. After its previous high-end graphics card, the Radeon HD 5970 got challenged by NVIDIA's GeForce GTX 580, which is unnoticeably slower, while being a lot more energy-efficient (since it's a single GPU graphics card). The red team just had to come up with something that makes up for that with a significant performance leadership over the GTX 580, so the 580's performance per watt advantage could be trumped with sheer performance.
In comes the Radeon HD 6990, the very peak of AMD's Northern Islands family of GPUs. It carries the codename "Antilles", and is a dual-GPU graphics card making use of two of AMD's "Cayman" graphics processors. Cayman in its single-GPU board designs make up for the rest of the HD 6900 series, namely HD 6950 and HD 6970. On AMD Radeon HD 6990, the Cayman chips have all 1536 of their stream processors based on the VLIW4 design enabled. Each GPU is backed by 2 GB of fast GDDR5 memory over a 256-bit wide memory interface each, totaling to 4 GB of total memory, the highest for a reference consumer graphics card launch.
Each of the Radeon HD 6990 GPUs are clocked at 830 MHz, with the memory at 1250 MHz (5000 MHz effective).
The ASUS EAH6990 we are testing today is a stick-to-the-book reference design Radeon HD 6990 from the company. It combines AMD’s fine choice of electrical components with a refreshingly clean visual appearance of the cooler and a complete set of accessories.
We also have a quad-GPU CrossFireX review of two of these cards here.
|Radeon HD 6990|
|Shader units||480||1536||512||2x 1600||2x 1536|
|ROPs||48||32||48||2x 32||2x 32|
|GPU||GF100||Cayman||GF110||2x Cypress||2x Cayman|
|Transistors||3200M||2640M||3000M||2x 2154M||2x 2640M|
|Memory Size||1536 MB||2048 MB||1536 MB||2x 1024 MB||2x 2048 MB|
|Memory Bus Width||384 bit||256 bit||384 bit||2x 256 bit||2x 256 bit|
|Core Clock||700 MHz||880 MHz||772 MHz||725 MHz||830 MHz|
|Memory Clock||924 MHz||1375 MHz||1002 MHz||1000 MHz||1250 MHz|