Sapphire Radeon HD 4850 X2 2G GDDR3

Name: Sapphire Radeon HD 4850 X2 2G GDDR3
Brand: Sapphire

by Marco Chiappetta — Wednesday, January 28, 2009, 11:15 AM EDT

Intro, Specs, and Bundle

When AMD launched the Radeon HD 4870 X2 a few months back, the company hinted at the impending release of another, more affordable, dual-GPU powered card aptly named the Radeon HD 4850 X2. Like the more powerful 4870 X2, the 4850 X2 would sport a pair of RV770 GPUs on a single PCB, but on the 4850 X2 they would be clocked somewhat lower and would be linked to more affordable GDDR3 memory.

At the time, AMD planned to release the card at a slightly lower price point than the competing GeForce GTX 280, but it took quite a while for the Radeon HD 4850 X2 to finally materialize. When it did arrive, in the form of the Sapphire Radeon HD 4850 X2 2G GDDR3 we'll be showing you here, the 3D graphics landscape had changed somewhat. While the two cards are still priced similarly, they are about $100 cheaper than originally planned.

Sapphire's interpretation of the Radeon HD 4850 X2 is also somewhat different than what we were originally shown during the 4870 X2 launch. AMD's reference Radeon HD 4850 X2 looked just like the 4870, with a similar cooler and dual, dual-link DVI outputs. Sapphire's version, however, has a custom dual-fan cooler, four DVI outputs, and an extra long PCB. Check it out...

Sapphire Radeon HD 4850 X2

Radeon HD 4850 / 4870 X2

Specifications and Features

956 million transistors on 55nm fabrication process
PCI Express 2.0 x16 bus interface
256-bit GDDR3/GDDR5 memory interface
Microsoft DirectX 10.1 support
- Shader Model 4.1
- 32-bit floating point texture filtering
- Indexed cube map arrays
- Independent blend modes per render target
- Pixel coverage sample masking
- Read/write multi-sample surfaces with shaders
- Gather4 texture fetching
Unified Superscalar Shader Architecture
- 800 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 160 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
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 (2, 4 or 8 samples per pixel)
- Up to 24x Custom Filter Anti-Aliasing (CFAA) for improved quality
- Adaptive super-sampling and multi-sampling
- Gamma correct
- Super AA (ATI CrossFireX 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 128 taps per pixel)
- 128-bit floating point HDR texture 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
ATI PowerPlay
- Advanced power management technology for optimal performance and power savings
- Performance-on-Demand
  - Constantly monitors GPU activity, dynamically adjusting clocks and voltage based on user scenario
  - Clock and memory speed throttling
  - Voltage switching
  - Dynamic clock gating
- Central thermal management – on-chip sensor monitors GPU temperature and triggers thermal actions as required

ATI Avivo HD Video and Display Platform

2nd generation Unified Video Decoder (UVD 2)
- Enabling hardware decode acceleration of H.264, VC-1 and MPEG-2
- Dual stream playback (or Picture-in-picture)
Hardware MPEG-1, and DivX video decode acceleration
- Motion compensation and IDCT
ATI Avivo Video Post Processor
- New enhanced DVD upconversion to HD new!
- New automatic and dynamic contrast adjustment new!
- Color space conversion
- Chroma subsampling format conversion
- Horizontal and vertical scaling
- Gamma correction
- Advanced vector adaptive per-pixel de-interlacing
- De-blocking and noise reduction filtering
- Detail enhancement
- Inverse telecine (2:2 and 3:2 pull-down correction)
- Bad edit correction
- Full score in HQV (SD) and HQV (HD) video quality benchmarks
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 DVI display outputs
- Primary supports 18-, 24-, and 30-bit digital displays at all resolutions up to 1920x1200 (single-link DVI) or 2560x1600 (dual-link DVI)
- Secondary supports 18-, 24-, and 30-bit digital displays at all resolutions up to 1920x1200 (single-link DVI only)3
- Each includes a dual-link HDCP encoder with on-chip key storage for high resolution playback of protected content4
Two integrated 400MHz 30-bit RAMDACs
- Each supports analog displays connected by VGA at all resolutions up to 2048x15363
DisplayPort output support
- Supports 24- and 30-bit displays at all resolutions up to 2560x16003
HDMI output support
- Supports all display resolutions up to 1920x10803
- Integrated HD audio controller with up to 2 channel 48 kHz stereo or multi-channel (7.1) AC3 enabling a plug-and-play cable-less audio solution
Integrated AMD Xilleon HDTV encoder
- Provides high quality analog TV output (component/S-video/composite)
- Supports SDTV and HDTV resolutions
- Underscan and overscan compensation
- 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
ATI CrossFireX Multi-GPU Technology
- Scale up rendering performance and image quality with two GPUs
- Integrated compositing engine
- High performance dual channel bridge interconnect
Before we dive in and inspect the Sapphire Radeon HD 4850 X2 2G GDDR3, we thought we'd show you what kind of bonus hardware and software Sapphire bundles with the card to sweeten the deal. Included with the Sapphire Radeon HD 4850 X2 we found a couple of Molex to 6- and 8-pin power adapters, a CrossFire bridge connector, an S-Video to composite adapter, an HD component output dongle, a DVI to HDMI adapter, a DVI to VGA adapter, a user's manual and a Sapphire case badge. In addition to the aforementioned items, Sapphire also throws in a quintet of discs, which include a Ruby ROM with some demos and a screensaver, 3DMark Vantage, a driver disc, and two discs from Cyberlink--one for their DVD Suite and another with PowerDVD. About the only thing missing is a full version game, but there is some useful stuff thrown in here that does add value.