GeForce GTX 660 vs Radeon HD 5870

Intro

Compare those specs to the Radeon HD 5870, which uses a 40 nm design. AMD has clocked the core frequency at 850 MHz. The GDDR5 memory is set to run at a speed of 1200 MHz on this particular card. It features 1600(320x5) SPUs along with 80 Texture Address Units and 32 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce GTX 660		140 Watts
Radeon HD 5870		188 Watts
	Difference: 48 Watts (34%)

Memory Bandwidth

Performance-wise, the Radeon HD 5870 should in theory be just a bit superior to the GeForce GTX 660 overall. (explain)

Radeon HD 5870		153600 MB/sec
GeForce GTX 660		144192 MB/sec
	Difference: 9408 (7%)

Texel Rate

The GeForce GTX 660 is a small bit (approximately 15%) better at AF than the Radeon HD 5870. (explain)

GeForce GTX 660		78400 Mtexels/sec
Radeon HD 5870		68000 Mtexels/sec
	Difference: 10400 (15%)

Pixel Rate

If running with high levels of AA is important to you, then the Radeon HD 5870 is a better choice, though only just barely. (explain)

Radeon HD 5870		27200 Mpixels/sec
GeForce GTX 660		23520 Mpixels/sec
	Difference: 3680 (16%)

Please note that the above 'benchmarks' are all just theoretical - the results were calculated based on the card's specifications, and real-world performance may (and probably will) vary at least a bit.

Price Comparison

Specifications

Memory Bandwidth: Memory bandwidth is the largest amount of data (counted in MB per second) that can be moved past the external memory interface within a second. The number is worked out by multiplying the bus width by its memory speed. If it uses DDR type RAM, the result should be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The higher the card's memory bandwidth, the better the card will be in general. It especially helps with AA, High Dynamic Range and higher screen resolutions.

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

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