Introduction

ATI's new Radeon HD 2900 or "R600" is probably the most hyped (and delayed) product of 2006 and 2007. The card uses the brand-new R600 GPU which is the first ATI product that has been specifically designed for DirectX10 and Windows Vista.

Here are all the specs at a glance, for further reference see our upcoming Radeon HD 2000 Series article.

Full Specifications

• 700 million transistors on 80nm HS fabrication process
• 512-bit 8-channel GDDR3/4 memory interface

Ring Bus Memory Controller

• Fully distributed design with 1024-bit internal ring bus for memory reads and writes
• Optimized for high performance HDR (High Dynamic Range) rendering at high display resolutions

Unified Superscalar Shader Architecture

• 320 stream processing units
• Dynamic load balancing and resource allocation for vertex, geometry, and pixel shaders
• Common instruction set and texture unit access supported for all types of shaders
• Dedicated branch execution units and texture address processors
• 128-bit floating point precision for all operations
• Command processor for reduced CPU overhead
• Shader instruction and constant caches
• Up to 80 texture fetches per clock cycle
• Up to 128 textures per pixel
• Fully associative multi-level texture cache design
• DXTC and 3Dc+ texture compression
• High resolution texture support (up to 8192 x 8192)
• Fully associative texture Z/stencil cache designs
• Double-sided hierarchical Z/stencil buffer
• Early Z test, Re-Z, Z Range optimization, and Fast Z Clear
• Lossless Z & stencil compression (up to 128:1)
• Lossless color compression (up to 8:1)
• 8 render targets (MRTs) with anti-aliasing support
• Physics processing support

Full support for Microsoft DirectX 10.0

• Shader Model 4.0
• Geometry Shaders
• Stream Output
• Integer and Bitwise Operations
• Alpha to Coverage
• Constant Buffers
• State Objects
• Texture Arrays

Dynamic Geometry Acceleration

• High performance vertex cache
• Programmable tessellation unit
• Accelerated geometry shader path for geometry amplification
• Memory read/write cache for improved stream output performance

Anti-aliasing features

• Multi-sample anti-aliasing (up to 8 samples per pixel)
• Up to 24x Custom Filter Anti-Aliasing (CFAA) for improved quality
• Adaptive super-sampling and multi-sampling
• Temporal anti-aliasing
• Gamma correct
• Super AA (CrossFire configurations only)
• All anti-aliasing features compatible with HDR rendering

Texture filtering features

• 2x/4x/8x/16x high quality adaptive anisotropic filtering modes (up to 128taps per pixel)
• 128-bit floating point HDR texture filtering
• Bicubic filtering
• sRGB filtering (gamma/degamma)
• Percentage Closer Filtering (PCF)
• Depth & stencil texture (DST) format support
• Shared exponent HDR (RGBE 9:9:9:5) texture format support

CrossFire™ Multi-GPU Technology

• Scale up rendering performance and image quality with 2 or more GPUs
• Integrated compositing engine
• High performance dual channel interconnect

ATI Avivo™ HD Video and Display Platform

• Two independent display controllers
• Drive two displays simultaneously with independent resolutions, refresh rates, color controls and video overlays for each display
• Full 30-bit display processing
• Programmable piecewise linear gamma correction, color correction, and color space conversion
• Spatial/temporal dithering provides 30-bit color quality on 24-bit and 18-bit displays
• High quality pre- and post-scaling engines, with underscan support for all display outputs
• Content-adaptive de-flicker filtering for interlaced displays
• Fast, glitch-free mode switching
• Hardware cursor
• Two integrated dual-link DVI display outputs
• Each supports 18-, 24-, and 30-bit digital displays at all resolutions up to 1920x1200 (single-link DVI) or 2560x1600 (dual-link DVI)
• Each includes a dual-link HDCP encoder with on-chip key storage for high resolution playback of protected content
• Two integrated 400 MHz 30-bit RAMDACs
• Each supports analog displays connected by VGA at all resolutions up to 2048x1536
• HDMI output support
• Supports all display resolutions up to 1920x1080
• Integrated HD audio controller with multi-channel (5.1) AC3 support, enabling a plug-and-play cable-less audio solution
• Integrated Xilleon™ HDTV encoder
• Provides high quality analog TV output (component/Svideo/ composite)
• Supports SDTV and HDTV resolutions
• Underscan and overscan compensation
• HD decode acceleration for H.264/AVC, VC-1, DivX and MPEG-2 video formats
• Flawless DVD, HD DVD, and Blu-Ray playback
• Motion compensation and IDCT (Inverse Discrete Cosine Transformation)
• HD video processing
• Advanced vector adaptive per-pixel de-interlacing
• De-blocking and noise reduction filtering
• Edge enhancement
• Inverse telecine (2:2 and 3:2 pull-down correction)
• Bad edit correction
• High fidelity gamma correction, color correction, color space conversion, and scaling
• MPEG-2, MPEG-4, DivX, WMV9, VC-1, and H.264/AVC encoding and transcoding
• Seamless integration of pixel shaders with video in real time
• VGA mode support on all display outputs

• PCI Express x16 bus interface
• OpenGL 2.0 support

When we received our sample a retail package was not available yet.

Our shipment had only the Radeon HD 2900 XT card and a DVI to HDMI (+audio) adapter.



The HDMI adapter is an extremely convenient solution for connecting your HDTV to the Radeon HD 2900 XT, unlike most previous solution the HDMI cable carries now audio and video. The audio is played back directly on the Radeon HD video card in a fully digital process, similar to SPDIF.

The Card

If we look at the size of the Radeon HD 2900 XT we see that it fits nicely in the middle of the GeForce 8800 GTX (left) and the Radeon X1900 XTX (right). First leaks have shown a behemoth PCB which obviously was too big to be used in the retail market, the big board may appear in OEM designs though.


The card's theme is still completely red, even though AMD's corporate colors are green, yet ATI remains red. On top of the cooler you can see a simple but pretty silvery flame paint job. The red transparent cooler reminds of the Radeon X1950 Series, the cooler inside has been changed of course.


On the back we see a big black metal heatsink which cools the memory chips on the back of the card. Yes you read right, the card goes back to the "memory chips on two sides" approach. This is because the memory bus bandwidth has been bumped to 512 bit which requires that you use 16 memory chips. Fitting all these on one side isn't possible, so each side has eight of them.


As you would expect, the card has two DVI outputs which are both dual-link capable, so highres displays up to 2560x1600 can be used. You can use both DVI outputs with HDMI adapters at the same time while still retaining HDCP encryption on both outputs. Also you can use the good old DVI to VGA adapters in case you still have a CRT or TFT with analog input.


The internal CrossFire connector is the same as on the Radeon X1950 Pro Series. All CrossFire handling is now done inside the GPU, an external CrossFire chip is no longer required, also all boards can run as CrossFire Master or Slave. Every retail board should include one CrossFire cable, so if you purchase two cards you will have the two bridges you need.