GeForce GTX 275 vs Radeon HD 7770

Intro

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

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 7770		80 Watts
GeForce GTX 275		219 Watts
	Difference: 139 Watts (174%)

Memory Bandwidth

Theoretically speaking, the GeForce GTX 275 should be 76% quicker than the Radeon HD 7770 overall, due to its greater bandwidth. (explain)

GeForce GTX 275		127008 MB/sec
Radeon HD 7770		72000 MB/sec
	Difference: 55008 (76%)

Texel Rate

The GeForce GTX 275 should be quite a bit (about 27%) better at AF than the Radeon HD 7770. (explain)

GeForce GTX 275		50640 Mtexels/sec
Radeon HD 7770		40000 Mtexels/sec
	Difference: 10640 (27%)

Pixel Rate

The GeForce GTX 275 will be just a bit (about 11%) better at AA than the Radeon HD 7770, and also will be capable of handling higher resolutions without losing too much performance. (explain)

GeForce GTX 275		17724 Mpixels/sec
Radeon HD 7770		16000 Mpixels/sec
	Difference: 1724 (11%)

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 information (counted in megabytes per second) that can be transferred past the external memory interface in a second. It's calculated by multiplying the card's interface width by its memory speed. In the case of DDR type RAM, the result should be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The higher the card's memory bandwidth, the better 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 are applied per second. This number is worked out by multiplying the total texture units of the card by the core clock 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 in one second.

Pixel Rate: Pixel rate is the maximum number of pixels that the graphics chip can possibly record to the local memory per second - measured in millions of pixels per second. The number is worked out by multiplying the number of Render Output Units by the the card's clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel output rate also depends on lots of other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to reach the max fill rate.