GeForce GTX 660 Ti vs Radeon HD 4850 2GB

Intro

Compare those specifications to the Radeon HD 4850 2GB, which comes with a clock frequency of 625 MHz and a GDDR4 memory speed of 993 MHz. It also uses a 256-bit memory bus, and makes use of a 55 nm design. It features 800(160x5) SPUs, 40 Texture Address Units, and 16 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 4850 2GB		110 Watts
GeForce GTX 660 Ti		150 Watts
	Difference: 40 Watts (36%)

Memory Bandwidth

The GeForce GTX 660 Ti should theoretically perform much faster than the Radeon HD 4850 2GB in general. (explain)

GeForce GTX 660 Ti		144000 MB/sec
Radeon HD 4850 2GB		63552 MB/sec
	Difference: 80448 (127%)

Texel Rate

The GeForce GTX 660 Ti will be a lot (about 310%) more effective at texture filtering than the Radeon HD 4850 2GB. (explain)

GeForce GTX 660 Ti		102480 Mtexels/sec
Radeon HD 4850 2GB		25000 Mtexels/sec
	Difference: 77480 (310%)

Pixel Rate

The GeForce GTX 660 Ti will be quite a bit (more or less 120%) better at AA than the Radeon HD 4850 2GB, and able to handle higher screen resolutions better. (explain)

GeForce GTX 660 Ti		21960 Mpixels/sec
Radeon HD 4850 2GB		10000 Mpixels/sec
	Difference: 11960 (120%)

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 maximum amount of data (counted in MB per second) that can be moved past the external memory interface in one second. It is worked out by multiplying the interface width by its memory clock speed. If it uses DDR memory, it should be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The higher the bandwidth is, the better the card will be in general. It especially helps with anti-aliasing, HDR and higher screen resolutions.

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

Pixel Rate: Pixel rate is the maximum amount of pixels the video card could possibly record to the local memory per second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the amount of colour ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - also 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, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to reach the maximum fill rate.