Radeon HD 3870 X2 512MB vs Radeon HD 6770 1GB

Intro

The Radeon HD 3870 X2 512MB comes with clock speeds of 825 MHz on the GPU, and 900 MHz on the 512 MB of GDDR3 RAM. It features 320(64x5) SPUs along with 16 Texture Address Units and 16 Rasterization Operator Units.

Compare all of that to the Radeon HD 6770 1GB, which comes with core clock speeds of 900 MHz on the GPU, and 1050 MHz on the 1024 MB of GDDR5 memory. It features 800 SPUs along with 40 TAUs and 16 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 3870 X2 512MB Amazon.com Other US-based stores Amazon.co.uk Amazon.de Amazon.fr

Radeon HD 6770 1GB Amazon.com Other US-based stores Amazon.co.uk Amazon.de Amazon.fr

Specifications

Model	Radeon HD 3870 X2 512MB	Radeon HD 6770 1GB
Manufacturer	ATi	ATi
Year	Jan 28, 2008	January 2011
Code Name	R680	Juniper XT
Fab Process	55 nm	40 nm
Bus	PCIe 2.0 x16/(internal PCIe 1.1 x16)	PCIe x16
Memory	512 MB (x2)	1024 MB
Core Speed	825 MHz (x2)	900 MHz
Shader Speed	N/A MHz (x2)	(N/A) MHz
Memory Speed	900 MHz (x2)	1050 MHz
Unified Shaders	320(64x5) (x2)	800
Texture Mapping Units	16 (x2)	40
Render Output Units	16 (x2)	16
Bus Type	GDDR3	GDDR5
Bus Width	256-bit (x2)	128-bit
DirectX Version	DirectX 10.1	DirectX 11
OpenGL Version	OpenGL 3.0	OpenGL 4.1
Power (Max TDP)	N/A watts	108 watts
Shader Model	4.1	5.0
Bandwidth	115200 MB/sec	67200 MB/sec
Texel Rate	26400 Mtexels/sec	36000 Mtexels/sec
Pixel Rate	26400 Mpixels/sec	14400 Mpixels/sec

Memory Bandwidth: Bandwidth is the largest amount of information (measured in megabytes per second) that can be transferred past the external memory interface within a second. It is worked out by multiplying the card's bus width by its memory speed. In the case of DDR memory, it must be multiplied by 2 again. If DDR5, multiply by 4 instead. The higher the card's memory bandwidth, the faster the card will be in general. It especially helps with AA, HDR and higher screen resolutions.

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

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