Radeon HD 5870 vs Radeon HD 6870

Intro

The Radeon HD 5870 makes use of a 40 nm design. AMD has clocked the core frequency at 850 MHz. The GDDR5 RAM works at a frequency of 1200 MHz on this specific card. It features 1600(320x5) SPUs as well as 80 Texture Address Units and 32 Rasterization Operator Units.

Compare all that to the Radeon HD 6870, which has core speeds of 900 MHz on the GPU, and 1050 MHz on the 1024 MB of GDDR5 memory. It features 1120 SPUs along with 56 TAUs and 32 ROPs.

Price Comparison

Radeon HD 5870 Amazon.com

Radeon HD 6870 Amazon.com

Please note that the price comparisons are based on search keywords - sometimes it might show cards with very similar names that are not exactly the same as the one chosen in the comparison. We do try to filter out the wrong results as best we can, though.

Specifications

Model	Radeon HD 5870	Radeon HD 6870
Manufacturer	AMD	AMD
Year	September 23, 2009	October 2010
Code Name	Cypress XT	Barts XT
Fab Process	40 nm	40 nm
Bus	PCIe 2.1 x16	PCIe x16
Memory	1024 MB	1024 MB
Core Speed	850 MHz	900 MHz
Shader Speed	N/A MHz	(N/A) MHz
Memory Speed	1200 MHz (4800 MHz effective)	1050 MHz (4200 MHz effective)
Unified Shaders	1600(320x5)	1120
Texture Mapping Units	80	56
Render Output Units	32	32
Bus Type	GDDR5	GDDR5
Bus Width	256-bit	256-bit
DirectX Version	DirectX 11	DirectX 11
OpenGL Version	OpenGL 3.2	OpenGL 4.1
Power (Max TDP)	188 watts	151 watts
Shader Model	5.0	5.0
Bandwidth	153600 MB/sec	134400 MB/sec
Texel Rate	68000 Mtexels/sec	50400 Mtexels/sec
Pixel Rate	27200 Mpixels/sec	28800 Mpixels/sec

Memory Bandwidth: Bandwidth is the max amount of data (counted in MB per second) that can be moved over the external memory interface in a second. It is calculated by multiplying the bus width by its memory clock speed. In the case of DDR RAM, it should be multiplied by 2 again. If DDR5, multiply by 4 instead. The better the memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, HDR and high resolutions.

Texel Rate: Texel rate is the maximum texture map elements (texels) that can be applied in one second. This figure is calculated by multiplying the total number of texture units of the card by the core speed of the chip. The better the texel rate, the better the graphics card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in one second.

Pixel Rate: Pixel rate is the most pixels the graphics card could possibly write to its local memory in one second - measured in millions of pixels per second. The figure is calculated by multiplying the number of ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel fill rate is also dependant on quite a few other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the potential to get to the max fill rate.