Radeon HD 4550 512MB vs Radeon HD 5450

Intro

Compare all of that to the Radeon HD 5450, which has a GPU core clock speed of 650 MHz, and 512 MB of DDR3 RAM set to run at 800 MHz through a 64-bit bus. It also is comprised of 80(16x5) SPUs, 8 TAUs, and 4 Raster Operation Units.

Display Graphs

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Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 5450		19 Watts
Radeon HD 4550 512MB		25 Watts
	Difference: 6 Watts (32%)

Memory Bandwidth

Both cards have the exact same bandwidth, so in theory they should have the same performance. (explain)

Texel Rate

The Radeon HD 5450 will be just a bit (approximately 8%) better at AF than the Radeon HD 4550 512MB. (explain)

Radeon HD 5450		5200 Mtexels/sec
Radeon HD 4550 512MB		4800 Mtexels/sec
	Difference: 400 (8%)

Pixel Rate

If running with a high screen resolution is important to you, then the Radeon HD 5450 is the winner, though only just barely. (explain)

Radeon HD 5450		2600 Mpixels/sec
Radeon HD 4550 512MB		2400 Mpixels/sec
	Difference: 200 (8%)

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 (in units of MB per second) that can be transported over the external memory interface within a second. It is calculated by multiplying the card's bus width by its memory speed. If it uses DDR memory, it must 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 anti-aliasing, HDR and higher screen resolutions.

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

Pixel Rate: Pixel rate is the maximum number of pixels the video card could possibly write to its local memory in one second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the number of Raster Operations Pipelines by the the core clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel fill rate also depends on quite a few other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the potential to reach the max fill rate.