14 DAY TRIAL // Rumors about the upcoming Radeon HD 6990 graphics card have made their way to the web ever since AMD has first announced the HD 6970 and HD 6950 back in November of last year, but now all these rumors can be put to rest as the official presentation slides of AMD's dual-GPU monster have been leaked, revealing all that we ever wanted to know about the card.
I will skip right over the visual examination of the board as AMD has released the first pictures of the HD 6990 yesterday, various review websites also posting picture previews of the card, so everyone even remotely interested should be familiar with Antilles by now.
This leads us straight to the HD 6990's specifications, and, as previous rumors pointed out, the card uses a pair of Cayman XT GPUs which are run at 830MHz, while the 4GB of GDDR5 memory are clocked at 1,250MHz.
The dual-Cayman core setup means that the card features 3072 stream processors, 192 texturing units and 64 ROPs as well as dual 256-bit memory buses with a total memory bandwidth of 307.2GB/s.
What's new about the HD 6990 is that AMD has decided to incorporate a dual-BIOS switch, which allows the user to switch from the regular operation mode to an overclocking mode.
This increases the voltage of the GPU to 1.175V (from the standard 1.12V) as well as the GPU's frequency to 880MHz.
Furthermore, AMD promises that the HD 6990 has been specially tuned in order to enable overclocks higher than 900MHz on the core and 1500MHZ on the memory (6000MHZ GDDR5 data rate).
To power this beast of a card, the power delivery circuitry had to be specially designed in order to supply the HD 6990 with 450W of power, so AMD used new Volterra regulators, which are now symmetrically positioned, and premium ASICs, screened for high speed and low leakage.
The cooling solution has also been upgraded to future dual vapor chambers, cooled by a central blower, the new design proving 20% more airflow than the HD 5970 while using the same form factor.
As far as performance goes, AMD expects the HD 6990, in OC mode, to be on average 67% faster than Nvidia's GTX 580 single-GPU graphics card.
The AMD Radeon HD 6990 will be made official on March 8. A few days later, during the PAX East game conference, Nvidia is expected to launch the dual-GPU GTX 590. (via Donanim Haber)
