Geforce GTX 780 vs Radeon R9 M275X

Intro

Compare all that to the Radeon R9 M275X, which has core speeds of 900 MHz on the GPU, and 1125 MHz on the 2048 MB of GDDR5 RAM. It features 640 SPUs as well as 40 Texture Address Units and 16 ROPs.

Display Graphs

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Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon R9 M275X		50 Watts
Geforce GTX 780		250 Watts
	Difference: 200 Watts (400%)

Memory Bandwidth

Performance-wise, the Geforce GTX 780 should in theory be quite a bit superior to the Radeon R9 M275X overall. (explain)

Geforce GTX 780		288384 MB/sec
Radeon R9 M275X		72000 MB/sec
	Difference: 216384 (301%)

Texel Rate

The Geforce GTX 780 will be a lot (approximately 360%) better at texture filtering than the Radeon R9 M275X. (explain)

Geforce GTX 780		165696 Mtexels/sec
Radeon R9 M275X		36000 Mtexels/sec
	Difference: 129696 (360%)

Pixel Rate

If using high levels of AA is important to you, then the Geforce GTX 780 is a better choice, by a large margin. (explain)

Geforce GTX 780		41424 Mpixels/sec
Radeon R9 M275X		14400 Mpixels/sec
	Difference: 27024 (188%)

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 maximum amount of data (measured in megabytes per second) that can be transported across the external memory interface within a second. It is calculated by multiplying the interface width by its memory clock speed. In the case of DDR memory, the result should be multiplied by 2 again. If DDR5, multiply by 4 instead. The better the memory bandwidth, the faster the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.

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

Pixel Rate: Pixel rate is the maximum amount of pixels the video card can possibly write to its local memory in one second - measured in millions of pixels per second. The number is worked out by multiplying the amount of Raster Operations Pipelines by the the core clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel fill rate also depends on quite a few 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.