GeForce GTX 660 vs Radeon HD 4870 2GB

Intro

Compare that to the Radeon HD 4870 2GB, which uses a 55 nm design. AMD has clocked the core speed at 750 MHz. The GDDR5 memory works at a speed of 900 MHz on this specific model. It features 800(160x5) SPUs as well as 40 TAUs and 16 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce GTX 660		140 Watts
Radeon HD 4870 2GB		150 Watts
	Difference: 10 Watts (7%)

Memory Bandwidth

The GeForce GTX 660, in theory, should perform quite a bit faster than the Radeon HD 4870 2GB overall. (explain)

GeForce GTX 660		144192 MB/sec
Radeon HD 4870 2GB		115200 MB/sec
	Difference: 28992 (25%)

Texel Rate

The GeForce GTX 660 will be quite a bit (about 161%) more effective at anisotropic filtering than the Radeon HD 4870 2GB. (explain)

GeForce GTX 660		78400 Mtexels/sec
Radeon HD 4870 2GB		30000 Mtexels/sec
	Difference: 48400 (161%)

Pixel Rate

The GeForce GTX 660 is quite a bit (about 96%) more effective at AA than the Radeon HD 4870 2GB, and should be capable of handling higher screen resolutions without losing too much performance. (explain)

GeForce GTX 660		23520 Mpixels/sec
Radeon HD 4870 2GB		12000 Mpixels/sec
	Difference: 11520 (96%)

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 largest amount of data (in units of MB per second) that can be transported over the external memory interface in a second. It's calculated by multiplying the card's interface width by its memory speed. If it uses DDR RAM, it must be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The higher the memory bandwidth, the better the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.

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

Pixel Rate: Pixel rate is the maximum number of pixels the video card can possibly record to the local memory in a second - measured in millions of pixels per second. The figure is worked out by multiplying the number of ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel fill rate is also dependant on lots of other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to get to the max fill rate.