GeForce 8400 GS 512MB vs Radeon HD 6770

Intro

Compare that to the Radeon HD 6770, which has a core clock speed of 900 MHz and a GDDR5 memory speed of 1050 MHz. It also makes use of a 128-bit bus, and makes use of a 40 nm design. It is made up of 800 SPUs, 40 Texture Address Units, and 16 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce 8400 GS 512MB		40 Watts
Radeon HD 6770		108 Watts
	Difference: 68 Watts (170%)

Memory Bandwidth

In theory, the Radeon HD 6770 will be 950% quicker than the GeForce 8400 GS 512MB overall, due to its higher data rate. (explain)

Radeon HD 6770		67200 MB/sec
GeForce 8400 GS 512MB		6400 MB/sec
	Difference: 60800 (950%)

Texel Rate

The Radeon HD 6770 is quite a bit (more or less 592%) better at texture filtering than the GeForce 8400 GS 512MB. (explain)

Radeon HD 6770		36000 Mtexels/sec
GeForce 8400 GS 512MB		5200 Mtexels/sec
	Difference: 30800 (592%)

Pixel Rate

If running with a high screen resolution is important to you, then the Radeon HD 6770 is the winner, by a large margin. (explain)

Radeon HD 6770		14400 Mpixels/sec
GeForce 8400 GS 512MB		2600 Mpixels/sec
	Difference: 11800 (454%)

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 largest amount of data (in units of MB per second) that can be transferred over the external memory interface in a second. It is worked out by multiplying the bus width by the speed of its memory. If the card has DDR memory, the result should be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The better the 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 texture map elements (texels) that can be processed in one second. This figure is calculated by multiplying the total texture units by the core clock speed of the chip. The better this number, the better the graphics 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 amount of pixels that the graphics chip can possibly write to its local memory in a second - measured in millions of pixels per second. The number is worked out by multiplying the number of Render Output Units by the the core speed of the card. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel rate is also dependant on many other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to reach the maximum fill rate.