GeForce GT 640 DDR3 vs Radeon HD 3470 512MB

Intro

Compare those specifications to the Radeon HD 3470 512MB, which has a GPU core clock speed of 800 MHz, and 512 MB of GDDR3 RAM set to run at 950 MHz through a 128-bit bus. It also is comprised of 40(8x5) Stream Processors, 4 TAUs, and 4 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

Theoretically speaking, the GeForce GT 640 DDR3 should be a lot faster than the Radeon HD 3470 512MB in general. (explain)

GeForce GT 640 DDR3		57024 MB/sec
Radeon HD 3470 512MB		30400 MB/sec
	Difference: 26624 (88%)

Texel Rate

The GeForce GT 640 DDR3 is a lot (approximately 800%) better at texture filtering than the Radeon HD 3470 512MB. (explain)

GeForce GT 640 DDR3		28800 Mtexels/sec
Radeon HD 3470 512MB		3200 Mtexels/sec
	Difference: 25600 (800%)

Pixel Rate

If running with a high screen resolution is important to you, then the GeForce GT 640 DDR3 is the winner, by far. (explain)

GeForce GT 640 DDR3		14400 Mpixels/sec
Radeon HD 3470 512MB		3200 Mpixels/sec
	Difference: 11200 (350%)

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 (in units of megabytes per second) that can be moved past the external memory interface within a second. It's worked out by multiplying the interface width by its memory speed. In the case of DDR memory, the result should be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The higher the bandwidth is, the faster the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and high resolutions.

Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are applied in one second. This number is calculated 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 graphics card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels per second.

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