GeForce GTX 660 vs Radeon HD 4850 1GB

Intro

Compare those specifications to the Radeon HD 4850 1GB, which makes use of a 55 nm design. AMD has clocked the core frequency at 625 MHz. The GDDR4 memory works at a frequency of 993 MHz on this card. It features 800(160x5) SPUs along with 40 TAUs and 16 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 4850 1GB		110 Watts
GeForce GTX 660		140 Watts
	Difference: 30 Watts (27%)

Memory Bandwidth

Theoretically, the GeForce GTX 660 should perform a lot faster than the Radeon HD 4850 1GB overall. (explain)

GeForce GTX 660		144192 MB/sec
Radeon HD 4850 1GB		63552 MB/sec
	Difference: 80640 (127%)

Texel Rate

The GeForce GTX 660 should be much (about 214%) more effective at texture filtering than the Radeon HD 4850 1GB. (explain)

GeForce GTX 660		78400 Mtexels/sec
Radeon HD 4850 1GB		25000 Mtexels/sec
	Difference: 53400 (214%)

Pixel Rate

The GeForce GTX 660 should be a lot (approximately 135%) more effective at anti-aliasing than the Radeon HD 4850 1GB, and also capable of handling higher resolutions while still performing well. (explain)

GeForce GTX 660		23520 Mpixels/sec
Radeon HD 4850 1GB		10000 Mpixels/sec
	Difference: 13520 (135%)

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 (counted in megabytes per second) that can be transported past the external memory interface within a second. It is calculated by multiplying the interface width by its memory speed. In the case of DDR RAM, the result should be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The better the bandwidth is, the better the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and high resolutions.

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

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