XFX and GIGABYTE RADEON HD 5970 CrossfireX Review :: Features

• 3200 Stream Processing Units
• 160 Texture Units
• 256 Z/Stencil ROP Units
• 64 Color ROP Units

• Shader Model 5.0
• DirectCompute 11
• Programmable hardware tessellation unit
• HDR texture compression
• Order-independent transparency

• Up to 24x multi-sample and super-sample anti-aliasing modes
• Adaptive anti-aliasing
Super AA
• 16x angle independent anisotropic texture filtering
• 128-bit floating point HDR rendering

• Three independent display controllers

• Drive three displays simultaneously with independent resolutions, refresh rates, color controls, and video overlays

• Display grouping

• Combine multiple displays to behave like a single large display

• OpenCL 1.0 compliant

• Dual, triple, and quad GPU scaling

• Max resolution: 2560x1600

• Max resolution: 1920x1200

• Max resolution: 2048x1536

• Output protected high bit rate 7.1 channel surround sound over HDMI with no additional cables required
• Supports AC-3, AAC, Dolby TrueHD and DTS Master Audio formats

• Dynamic power management with low power idle state
• Ultra-low power state support for multi-GPU configurations
• Certified drivers for Windows 7, Windows Vista, and Windows XP
• Engine clock speed: 725 MHz
• Processing power (single precision): 4.64 TeraFLOPS
• Processing power (double precision): 928 GigaFLOPS
• Polygon throughput: 1.45 billion polygons/sec
• Data fetch rate (32-bit): 464 billion fetches/sec
• Texel fill rate (bilinear filtered): 116 Gigatexels/sec
• Pixel fill rate: 46.4 Gigapixels/sec
• Anti-aliased pixel fill rate: 185.6 Gigasamples/sec
• Memory clock speed: 1.0 GHz
• Memory data rate: 4.0 Gbps
• Memory bandwidth: 256.0 GB/sec
• Maximum board power: 294 Watts
• Idle board power: 51 Watts

Each of the HD 5970s is based upon ATI’s Evergreen family of cards. The HD 5970 is codenamed Hemlock consisting of two of the Juniper XT chips used in the HD 5870 cards. Each chip has its own memory controller and is a separate chip on the card with a bridge chip allowing the two chips to communicate with each other in Crossfire mode.

Each of the Juniper XT chips is manufactured on TSMC’s 40nm process and has 2.1 Billion transistors. The Juniper XT chip has 1600 Stream Processors, meaning that four of them will have 6400 SPs, an unheard of amount of SPs two video cards. The previous generation HD 4890 had a total of 800 SPs, meaning two HD 5970s should provide great performance in every respect.

The memory bus on the HD 5970 is 256-bit for each video chip. This means that the HD 5970 CrossfireX combination offers 128GB of memory bandwidth to each of the four cards. GDDR5 memory is rated for double the bandwidth offered by GDDR3 memory meaning that though the cards memory is clocked at 1GHz, it offers the same bandwidth as 2GHz GDDR3 memory. The two cards have 4GB of memory between them each chip having its own 1GB of memory assigned to it.

The major new feature of the HD 5xxx series from ATI is support for DirectX 11 from Microsoft. DirectX 11 brings support for Multi-Threading, Shader Model 5.0, DirectCompute, and much more. Multi-thread performance means that the card can take advantage of more CPU cores on the CPU as most applications are limited to single threaded performance today. DirectCompute allows the graphics card to be used for computationally intense programs and allows the program writer to use the many cores of the GPU to perform calculations.

Eyefinity is a new technology from ATI that allows the user to use multiple desktop monitors to display images from one or more ATI card. Most HD 5xxx cards can do three simultaneous monitors with the use of a DisplayPort. There are HD 5870 cards that can use up to six monitors, but all must be connected to the Display Ports, as the card I/O plate does not have the necessary room to include display connectors bigger than a DisplayPort.

One issue with multiple graphics cards is the amount of power that two cards consume. ATI says that the HD 5970 consumes 294W of power maximum and have a Certified list of Power Supplies that they recommend for those wanting to use two 5970s in CrossfireX mode. AMD recommends at least a 625W PSU for two HD 4870 x2s but I would suggest more is better especially with four HD 5870 chips on the setup and a powerful CPU in the mix as well.

GPUZ

All setting

AA

AA setting

The HD 5870 is capable of doing 8x FSAA by itself. Two of the chips on the HD 5970 can do 16x FSAA, but the limitation is maxed out at 16x FSAA. ATI has improved the way image quality looks on the HD 5xxx cards with SuperSample AA available as an option in the AA Mode menu. SuperSample AA gives a higher image quality than MSAA but also costs more in terms of performance. With four HD 5870 chips used in two 5970 CrossfireX mode, this shouldn’t be a problem.