GeForce GTX 660 Ti vs Radeon HD 7770

Intro

Compare those specifications to the Radeon HD 7770, which features clock speeds of 1000 MHz on the GPU, and 1125 MHz on the 1024 MB of GDDR5 RAM. It features 640 SPUs along with 40 TAUs and 16 Rasterization Operator Units.

(No game benchmarks for this combination yet.)

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 7770		80 Watts
GeForce GTX 660 Ti		150 Watts
	Difference: 70 Watts (88%)

Memory Bandwidth

Theoretically speaking, the GeForce GTX 660 Ti will be 100% faster than the Radeon HD 7770 overall, due to its greater bandwidth. (explain)

GeForce GTX 660 Ti		144000 MB/sec
Radeon HD 7770		72000 MB/sec
	Difference: 72000 (100%)

Texel Rate

The GeForce GTX 660 Ti should be quite a bit (about 156%) better at AF than the Radeon HD 7770. (explain)

GeForce GTX 660 Ti		102480 Mtexels/sec
Radeon HD 7770		40000 Mtexels/sec
	Difference: 62480 (156%)

Pixel Rate

The GeForce GTX 660 Ti will be much (more or less 37%) more effective at FSAA than the Radeon HD 7770, and should be able to handle higher screen resolutions better. (explain)

GeForce GTX 660 Ti		21960 Mpixels/sec
Radeon HD 7770		16000 Mpixels/sec
	Difference: 5960 (37%)

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 max amount of data (measured in megabytes per second) that can be moved past the external memory interface in one second. The number is worked out by multiplying the bus width by the speed of its memory. In the case of DDR memory, the result 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 anti-aliasing, HDR and higher screen resolutions.

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

Pixel Rate: Pixel rate is the maximum number of pixels the graphics card could possibly record to the local memory in a second - measured in millions of pixels per second. The number is calculated by multiplying the amount of Render Output Units by the the core clock speed. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate is also dependant on lots of other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to get to the maximum fill rate.