Radeon HD 6870 vs Radeon HD 7870

Intro

The Radeon HD 6870 makes use of a 40 nm design. ATi has set the core speed at 900 MHz. The GDDR5 memory is set to run at a speed of 1050 MHz on this particular card. It features 1120 SPUs as well as 56 TAUs and 32 Rasterization Operator Units.

Compare those specs to the Radeon HD 7870, which features GPU core speed of 1000 MHz, and 2048 MB of GDDR5 RAM set to run at 1200 MHz through a 256-bit bus. It also features 1280 Stream Processors, 80 TAUs, and 32 ROPs.

Price Comparison

Please note that the price comparisons are based on search keywords, and might not be the exact same card listed on this page. We have no control over the accuracy of their search results.

Radeon HD 6870 Amazon.com Other US-based stores Amazon.co.uk Amazon.de Amazon.fr

Radeon HD 7870 Amazon.com Other US-based stores Amazon.co.uk Amazon.de Amazon.fr

Specifications

Model	Radeon HD 6870	Radeon HD 7870
Manufacturer	ATi	ATi
Year	October 2010	March 2012
Code Name	Barts XT	Pitcairn XT
Fab Process	40 nm	28 nm
Bus	PCIe x16	PCIe 3.0 x16
Memory	1024 MB	2048 MB
Core Speed	900 MHz	1000 MHz
Shader Speed	N/A MHz	(N/A) MHz
Memory Speed	1050 MHz (4200 MHz effective)	1200 MHz (4800 MHz effective)
Unified Shaders	1120	1280
Texture Mapping Units	56	80
Render Output Units	32	32
Bus Type	GDDR5	GDDR5
Bus Width	256-bit	256-bit
DirectX Version	DirectX 11	DirectX 11.1
OpenGL Version	OpenGL 4.1	OpenGL 4.2
Power (Max TDP)	151 watts	175 watts
Shader Model	5.0	5.0
Bandwidth	134400 MB/sec	153600 MB/sec
Texel Rate	50400 Mtexels/sec	80000 Mtexels/sec
Pixel Rate	28800 Mpixels/sec	32000 Mpixels/sec

Memory Bandwidth: Bandwidth is the maximum amount of information (in units of MB per second) that can be moved over the external memory interface in a second. It's worked out by multiplying the bus width by its memory clock speed. If it uses DDR type memory, it must be multiplied by 2 again. If DDR5, multiply by 4 instead. The better the memory bandwidth, the better the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.

Texel Rate: Texel rate is the maximum texture map elements (texels) that can be applied per second. This is worked out by multiplying the total number of texture units by the core clock speed of the chip. The better this number, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied per second.

Pixel Rate: Pixel rate is the maximum amount of pixels the video card could possibly record to its local memory in a second - measured in millions of pixels per second. The figure is calculated by multiplying the number of ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel fill rate also depends on many other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the ability to reach the maximum fill rate.