Radeon HD 4550 512MB vs Radeon HD 6750

Intro

Compare that to the Radeon HD 6750, which features GPU core speed of 725 MHz, and 512 MB of GDDR5 RAM running at 1000 MHz through a 128-bit bus. It also is comprised of 720 Stream Processors, 36 Texture Address Units, and 16 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 4550 512MB		25 Watts
Radeon HD 6750		86 Watts
	Difference: 61 Watts (244%)

Memory Bandwidth

In theory, the Radeon HD 6750 is 400% quicker than the Radeon HD 4550 512MB overall, because of its higher bandwidth. (explain)

Radeon HD 6750		64000 MB/sec
Radeon HD 4550 512MB		12800 MB/sec
	Difference: 51200 (400%)

Texel Rate

The Radeon HD 6750 should be quite a bit (about 444%) more effective at anisotropic filtering than the Radeon HD 4550 512MB. (explain)

Radeon HD 6750		26100 Mtexels/sec
Radeon HD 4550 512MB		4800 Mtexels/sec
	Difference: 21300 (444%)

Pixel Rate

If running with high levels of AA is important to you, then the Radeon HD 6750 is the winner, by far. (explain)

Radeon HD 6750		11600 Mpixels/sec
Radeon HD 4550 512MB		2400 Mpixels/sec
	Difference: 9200 (383%)

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 max amount of information (in units of MB per second) that can be transferred past the external memory interface within a second. It's worked out by multiplying the bus width by the speed of its memory. If it uses DDR memory, the result should be multiplied by 2 once again. If DDR5, multiply by 4 instead. The higher the card's memory bandwidth, the faster the card will be in general. It especially helps with AA, HDR and high 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 number of texture units by the core clock speed of the chip. The better this number, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels in one second.

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