GeForce GTX 660 vs Radeon HD 7870

Intro

The GeForce GTX 660 makes use of a 28 nm design. nVidia has set the core frequency at 980 MHz. The GDDR5 memory is set to run at a speed of 1502 MHz on this particular card. It features 960 SPUs as well as 80 Texture Address Units and 24 Rasterization Operator Units.

Compare those specifications to the Radeon HD 7870, which features GPU clock speed of 1000 MHz, and 2048 MB of GDDR5 RAM running at 1200 MHz through a 256-bit bus. It also is comprised of 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.

GeForce GTX 660 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	GeForce GTX 660	Radeon HD 7870
Manufacturer	nVidia	ATi
Year	September 2012	March 2012
Code Name	GK106	Pitcairn XT
Fab Process	28 nm	28 nm
Bus	PCIe 3.0 x16	PCIe 3.0 x16
Memory	2048 MB	2048 MB
Core Speed	980 MHz	1000 MHz
Shader Speed	980 MHz	(N/A) MHz
Memory Speed	1502 MHz (6008 MHz effective)	1200 MHz (4800 MHz effective)
Unified Shaders	960	1280
Texture Mapping Units	80	80
Render Output Units	24	32
Bus Type	GDDR5	GDDR5
Bus Width	192-bit	256-bit
DirectX Version	DirectX 11.1	DirectX 11.1
OpenGL Version	OpenGL 4.3	OpenGL 4.2
Power (Max TDP)	140 watts	175 watts
Shader Model	5.0	5.0
Bandwidth	144192 MB/sec	153600 MB/sec
Texel Rate	78400 Mtexels/sec	80000 Mtexels/sec
Pixel Rate	23520 Mpixels/sec	32000 Mpixels/sec

Memory Bandwidth: Bandwidth is the max amount of information (in units of MB per second) that can be moved across the external memory interface in a second. It is calculated by multiplying the interface width by the speed of its memory. In the case of DDR type RAM, it should be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The better the card's memory bandwidth, the faster the card will be in general. It especially helps with AA, HDR and high resolutions.

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

Pixel Rate: Pixel rate is the most pixels that the graphics chip could possibly write to the local memory per second - measured in millions of pixels per second. The figure is calculated by multiplying the amount of ROPs by the clock speed of the card. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate is also dependant on lots of other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the potential to reach the max fill rate.