Table of Contents:
• 1.7 Billion Transistors
• 1120 Stream Processors
• 14 SIMD Engines
• 56 Texture units
• 128 Z/Stencil ROPs
• 32 Color ROPs
• Max Board Power 151W
• Idle Power 19W
• 1GB GDDR5
• Dual 6-pin power
• 2x DVI, 2x Mini-DisplayPort, HDMI
• 900MHz Core Clock speed
• 1.05GB/second memory clock speed
• 134.4GB/second memory bandwidth
• Updated Tessellation unit
• 2TeraFLOPS computing power
• 28.8 Gigapixels/second pixel rate
• 50.4Gigatexels/second texture rate
• Dual Rasterizers
• 256-bit GDDR5 memory interface
• Morphological Anti-Aliasing
• Blu-ray 3D
• HDMI 1.4a
• DisplayPort 1.2
The new AMD HD 6870 is based upon their Northern Islands architecture, with a chip codenamed Barts XT. The Barts chip starts off with AMD’s familiar 16 SP SIMD, which is capable of four operations, a clock plus a Multiply ADD operation, a clock for five processors per SP. So each SIMD unit has 80 Stream Processors. There are two configurations launching today, the HD 6870 and the HD 6850.
The HD 6870 has 14 SIMDs with 80 SPs each for a total of 1120 Stream Processors. The HD 6850 has two less SIMDs with 12 each having 80 SPs for a total of 960 SPs. The HD 6870 card has 56 texture units, 32 ROPs and 128 Z/Stencil ROPs. AMD says that their card can do 2 TeraFLOPS/second of computing power compared to the 1.75 TeraFLOPS a second on the HD 6850. The fill rate of the card is 24.8 Gigapixels/second.
AMD is really pushing the envelope with their Eyespeed technology. This combines their UVD3 video processing engine with their parallel processing found on the HD 6870 to offer acceleration for applications like Office 2010, IE 9, Firefox 4, video editing and transcoding and video acceleration for Blu-ray 3D, DivX, and DVD Up-scaling. These are all applications that everyone uses and acceleration for such applications is always welcome.
The HD 6870 has a memory speed of 4.2GHz compared to the 4.0GHz clock speed on the HD 6850 using a 256-bit memory bus. The HD 6870 has a memory bandwidth of 134.4GB/second while the HD 6850 has a memory bandwidth of 128GB/second. Now mind you this card is targeted at the sweet spot of the gaming market in between $199 for the HD 6850 and $249 for the HD 6870 reference cards. This should offer near the same performance of the 5850 for a lower price point on a smaller die.
One improvement AMD has made with their HD 6 series is the improved Tessellation performance. The HD 6870 and 6850 have up to 2x the performance in Tessellation over the HD 5870 series in differing situations. This means improved performance in DirectX 11 games over the previous generation as games like HAWX2 which uses a lot of tessellation throughout the game and Aliens Versus Predator, which uses tessellation throughout, will benefit from increased performance in this regard.
3D is really taking off with the release of 3D Televisions, and Blu-ray 3D. NVIDIA introduced 3D Vision last year to their graphics cards to support 3D gaming on while using stereoscopic glasses and a 120Hz monitor. AMD introduced support for their version of 3D with the HD 5 series but hasn’t gotten much traction. With the launch of the HD 6 series AMD is moving towards bringing support for Blu-ray 3D support and stereoscopic 3D support for games with over 35 DisplayPort products, 45 validated and ready titles with hundreds of compatible games and affordable Single-Link DP to DVI adapters to allow for stereoscopic 3D on a budget.
Anti-aliasing improves the image quality of a game by removing the jaggies and image artifacts from a game or application. Current methods of anti-aliasing include supersample anti-aliasing, which ups the internal resolution by the number of samples and downsamples the resulting image. Multi-Sample anti-aliasing each pixel at the edge of a polygon is sampled multiple times. For each sample pass a slight offset is applied to all screen coordinates. By averaging all of these samples the result is a smoother transition of the colors at the edges. The number of samples taken for each pixel indicates the level of multisampling, so 4x is 4 samples from each pixel at the edge of a polygon. AMD is introducing a new feature with the HD 6 series called Morphological Anti-aliasing. MLAA adds a post-processing pass on the fully rendered image and anti-alias the sharp edges using DirectCompute. All AMD DirectX 11 cards support this new technique from the HD 5450 to the highest end cards.