GeForce GTX 660 vs Radeon HD 6850

Intro

Compare those specifications to the Radeon HD 6850, which comes with a core clock frequency of 775 MHz and a GDDR5 memory speed of 1000 MHz. It also uses a 256-bit memory bus, and makes use of a 40 nm design. It is comprised of 960 SPUs, 48 Texture Address Units, and 32 Raster Operation Units.

Display Graphs

Hide Graphs

Benchmarks

These are real-world performance benchmarks that were submitted by Hardware Compare users. The scores seen here are the average of all benchmarks submitted for each respective test and hardware.

3DMark Fire Strike Graphics Score

GeForce GTX 660		5063 points
Radeon HD 6850		2395 points
	Difference: 2668 (111%)

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 6850		127 Watts
GeForce GTX 660		140 Watts
	Difference: 13 Watts (10%)

Memory Bandwidth

In theory, the GeForce GTX 660 will be 13% faster than the Radeon HD 6850 in general, due to its greater bandwidth. (explain)

GeForce GTX 660		144192 MB/sec
Radeon HD 6850		128000 MB/sec
	Difference: 16192 (13%)

Texel Rate

The GeForce GTX 660 should be quite a bit (approximately 111%) more effective at anisotropic filtering than the Radeon HD 6850. (explain)

GeForce GTX 660		78400 Mtexels/sec
Radeon HD 6850		37200 Mtexels/sec
	Difference: 41200 (111%)

Pixel Rate

If running with lots of anti-aliasing is important to you, then the Radeon HD 6850 is a better choice, not by a very large margin though. (explain)

Radeon HD 6850		24800 Mpixels/sec
GeForce GTX 660		23520 Mpixels/sec
	Difference: 1280 (5%)

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: Bandwidth is the maximum amount of data (in units of MB per second) that can be transferred over the external memory interface within a second. The number is calculated by multiplying the bus width by the speed of its memory. If the card has DDR type memory, it should be multiplied by 2 once again. If DDR5, multiply by 4 instead. The higher the memory bandwidth, the faster 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 number of texture map elements (texels) that can be processed per second. This figure is worked out by multiplying the total number of texture units of the card 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 a 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 amount of Raster Operations Pipelines by the the core speed of the card. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate also depends on quite a few other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the potential to reach the max fill rate.