GeForce GTX 660 vs Radeon HD 7970

Intro

The GeForce GTX 660 has a GPU core clock speed of 980 MHz, and the 2048 MB of GDDR5 memory is set to run at 1502 MHz through a 192-bit bus. It also is comprised of 960 Stream Processors, 80 Texture Address Units, and 24 Raster Operation Units.

Compare all that to the Radeon HD 7970, which features a core clock speed of 925 MHz and a GDDR5 memory speed of 1375 MHz. It also uses a 384-bit memory bus, and uses a 28 nm design. It is comprised of 2048 SPUs, 128 Texture Address Units, 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.

GeForce GTX 660 Amazon.com Other US-based stores Amazon.co.uk Amazon.de Amazon.fr

Radeon HD 7970 Amazon.com Other US-based stores Amazon.co.uk Amazon.de Amazon.fr

Specifications

Model	GeForce GTX 660	Radeon HD 7970
Manufacturer	nVidia	ATi
Year	September 2012	January 2012
Code Name	GK106	Tahiti XT
Fab Process	28 nm	28 nm
Bus	PCIe 3.0 x16	PCIe 3.0 x16
Memory	2048 MB	3072 MB
Core Speed	980 MHz	925 MHz
Shader Speed	980 MHz	(N/A) MHz
Memory Speed	1502 MHz (6008 MHz effective)	1375 MHz (5500 MHz effective)
Unified Shaders	960	2048
Texture Mapping Units	80	128
Render Output Units	24	32
Bus Type	GDDR5	GDDR5
Bus Width	192-bit	384-bit
DirectX Version	DirectX 11.1	DirectX 11.1
OpenGL Version	OpenGL 4.3	OpenGL 4.2
Power (Max TDP)	140 watts	250 watts
Shader Model	5.0	5.0
Bandwidth	144192 MB/sec	264000 MB/sec
Texel Rate	78400 Mtexels/sec	118400 Mtexels/sec
Pixel Rate	23520 Mpixels/sec	29600 Mpixels/sec

Memory Bandwidth: Bandwidth is the largest amount of information (in units of megabytes per second) that can be transferred past the external memory interface within a second. It's worked out by multiplying the bus width by its memory speed. If it uses DDR type RAM, it must be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The better the 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 number of texture map elements (texels) that can be applied per second. This is calculated by multiplying the total number of texture units by the core clock speed of the chip. The better this number, the better the video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in a second.

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