ATI Radeon HD 4870

ATI Radeon HD 4870

RADEON HD 4870

• Codename: RV770-2
• Process technology: 55 nm
• 956 million transistors
• Unified architecture with an array of common processors for streaming processing of vertices and pixels, as well as other data
• Hardware support for DirectX 10.1, including new Shader Model 4.1, geometry generation, and stream output
• 256-bit memory bus: four 64-bit controllers supporting GDDR3/GDDR5
• Core clock: 750 MHz
• 10 SIMD cores, including 800 scalar floating-point ALUs (integer and floating-point formats, support for FP32 and FP64 in compliance with IEEE 754)
• 10 enlarged texture units supporting FP16 and FP32 formats
• 40 texture address units
• 160 texture fetch units
• 40 bilinear filtering units that can filter FP16 textures at full speed, trilinear and anisotropic filtering for all texture formats
• Dynamic branching in pixel and vertex shaders
• 16 ROPs supporting antialiasing with programmable sample patterns (over 16 samples per pixel), including FP16 or FP32 formats of the frame buffer. Peak performance is up to 16 samples per cycle (including MSAA 2x/4x and FP16 buffers), 64 samples per cycle in Z only mode
• Writing results up to eight frame buffers simultaneously (MRT)
• Integrated support for two RAMDACs, two Dual Link DVIs, HDMI, HDTV, DisplayPort

RADEON HD 4870 Specifications

• Core clock: 750 MHz
• Unified processors: 800
• 40 texture units, 16 blending units
• Effective memory frequency: 3600 MHz (4*900 MHz)
• Memory type: GDDR5
• Memory: 512 MB
• Memory bandwidth: 115 GB/sec
• Maximum theoretical fillrate: 12.0 gigapixel per second
• Theoretical texture sampling rate: 30.0 gigatexel per second
• 2 x CrossFireX connectors
• PCI Express 2.0 x16 bus
• 2 x DVI-I Dual Link, 2560x1600 video output
• TV-Out, HDTV-Out, support for HDCP, HDMI, DisplayPort
• Power consumption: up to 160 W (two 6-pin connectors)
• Two-slot design
• Recommended price: $299

As you may have noticed, we publish articles related to 48xx series with much delay, for which AMD is to be blamed. Inviting mass media five days prior to the announcement and then shifting the event is pure disrespect to IT reviewers. To all appearances, the marketing department forgot that users and retailers do have to read mass media publications to learn about new products. They changed the announcement date only because HD 4850 based products have already leaked into retail channel.

This actually ruined our review schedule. Alexey Berillo brought a sample from the event only on June 20 - the day this series was announced. With HD 4870 it was even worse: cards got stuck at the customs somewhere in Europe and were delivered to Russia already too late - only to be stuck at the local customs. What a pity. As you can see, that's not our bias in any way, that's just the way it is.

Anyway, HIS has kindly provided us with a sample of HD 4870, so we can finally publish our test results.