|Sapphire 100310SR Radeon HD 6990|
|Reviews - Featured Reviews: Video Cards|
|Written by Olin Coles|
|Wednesday, 16 March 2011|
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Antilles Detailed Features
In the image below, we've included an exposed PCB illustration supplied by AMD. According to their media presentation, the Radeon HD 6990 uses a special phase-change thermal interface material that loses its effectiveness once the heatsink has been removed. Used in conjunction with an improved cooling solution, according to AMD the Radeon HD 6990 yields 8% better thermal performance when compared to previous thermal management solutions they've used. Click on the image below for a larger high-resolution version.
The redesigned cooling solution on Antilles uses two independent heatsinks mounted between a blower motor fan to cool each Cayman GPU. Will this be enough? We reveal our temperature testing results later on in this article.
Antilles uses two 40nm Cayman GPUs on the Radeon HD 6990. Each GPU is clocked to 830 MHz by default, but can be switched to 880 MHz using the dual-BIOS. Additionally, AMD's PowerTune software allows the same options through the Catalyst Control Center.
A pair of Cooper Bussmann coupled inductors labeled with CLA1108-4-50TR-R markings are surrounded by what AMD is referring to as digital programmable regulators made by Volterra Semiconductor.
The AMD Radeon HD 6990 features 4GB GDDR5 video frame buffer memory, supplied by several Hynix H5GQ2H24MFR-T2C components. Hynix defines the speed of these parts using the T2C indicator code, which represents 2.5 GHz. According to Hynix, this GDDR5 graphics memory can reach 5.0 Gbps bandwidth with 1.5V or 3.6 Gbps with 1.35V, depending on voltage applied.
AMD clocks the GDDR5 to 1250 MHz, regardless of dual-BIOS switch position. By creating a custom BIOS, or by using software tools, hardware enthusiasts can further tweak the performance of their Radeon HD 6990.