GeForce 9400 GT 256MB vs Radeon HD 6790

Intro

Compare all of that to the Radeon HD 6790, which has core speeds of 840 MHz on the GPU, and 1050 MHz on the 1024 MB of GDDR5 RAM. It features 800 SPUs along with 40 Texture Address Units and 16 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce 9400 GT 256MB		50 Watts
Radeon HD 6790		150 Watts
	Difference: 100 Watts (200%)

Memory Bandwidth

Performance-wise, the Radeon HD 6790 should theoretically be much superior to the GeForce 9400 GT 256MB in general. (explain)

Radeon HD 6790		134400 MB/sec
GeForce 9400 GT 256MB		12800 MB/sec
	Difference: 121600 (950%)

Texel Rate

The Radeon HD 6790 is much (about 664%) faster with regards to texture filtering than the GeForce 9400 GT 256MB. (explain)

Radeon HD 6790		33600 Mtexels/sec
GeForce 9400 GT 256MB		4400 Mtexels/sec
	Difference: 29200 (664%)

Pixel Rate

If running with lots of anti-aliasing is important to you, then the Radeon HD 6790 is the winner, by a large margin. (explain)

Radeon HD 6790		13440 Mpixels/sec
GeForce 9400 GT 256MB		2200 Mpixels/sec
	Difference: 11240 (511%)

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 megabytes per second) that can be moved over the external memory interface in a second. It's calculated by multiplying the card's interface width by the speed of its memory. If the card has DDR type memory, it should be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The higher the card's memory bandwidth, the faster 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 amount of texture map elements (texels) that are applied per second. This number is calculated by multiplying the total texture units by the core clock speed of the chip. The better the texel rate, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels in a second.

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