Radeon HD 4670 1GB vs Radeon HD 4850 512MB

Intro

Compare that to the Radeon HD 4850 512MB, which comes with a GPU core clock speed of 625 MHz, and 512 MB of GDDR3 RAM set to run at 993 MHz through a 256-bit bus. It also is comprised of 800(160x5) Stream Processors, 40 Texture Address Units, and 16 Raster Operation Units.

Display Graphs

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Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 4670 1GB		70 Watts
Radeon HD 4850 512MB		110 Watts
	Difference: 40 Watts (57%)

Memory Bandwidth

The Radeon HD 4850 512MB should theoretically be quite a bit faster than the Radeon HD 4670 1GB in general. (explain)

Radeon HD 4850 512MB		63552 MB/sec
Radeon HD 4670 1GB		35200 MB/sec
	Difference: 28352 (81%)

Texel Rate

The Radeon HD 4850 512MB is a bit (about 4%) better at AF than the Radeon HD 4670 1GB. (explain)

Radeon HD 4850 512MB		25000 Mtexels/sec
Radeon HD 4670 1GB		24000 Mtexels/sec
	Difference: 1000 (4%)

Pixel Rate

If running with a high screen resolution is important to you, then the Radeon HD 4850 512MB is a better choice, by a large margin. (explain)

Radeon HD 4850 512MB		10000 Mpixels/sec
Radeon HD 4670 1GB		6000 Mpixels/sec
	Difference: 4000 (67%)

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 max amount of data (in units of megabytes per second) that can be transferred past the external memory interface within a second. The number is worked out by multiplying the bus width by the speed of its memory. In the case of DDR type RAM, the result should be multiplied by 2 again. If DDR5, multiply by 4 instead. The higher the bandwidth is, the faster the card will be in general. It especially helps with AA, HDR and higher screen resolutions.

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

Pixel Rate: Pixel rate is the most pixels that the graphics card could possibly write to its local memory per second - measured in millions of pixels per second. The number is calculated by multiplying the number of ROPs by the clock 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 fill rate is also dependant on quite a few other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the potential to reach the max fill rate.