Radeon HD 4550 256MB vs Radeon HD 5450

Intro

Compare all that to the Radeon HD 5450, which features a core clock speed of 650 MHz and a DDR3 memory frequency of 800 MHz. It also makes use of a 64-bit memory bus, and makes use of a 40 nm design. It is comprised of 80(16x5) SPUs, 8 TAUs, and 4 ROPs.

Display Graphs

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Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 5450		19 Watts
Radeon HD 4550 256MB		25 Watts
	Difference: 6 Watts (32%)

Memory Bandwidth

Both cards have exactly the same memory bandwidth, so theoretically they should perform the same. (explain)

Texel Rate

The Radeon HD 5450 is a small bit (about 8%) more effective at AF than the Radeon HD 4550 256MB. (explain)

Radeon HD 5450		5200 Mtexels/sec
Radeon HD 4550 256MB		4800 Mtexels/sec
	Difference: 400 (8%)

Pixel Rate

The Radeon HD 5450 will be just a bit (approximately 8%) better at FSAA than the Radeon HD 4550 256MB, and able to handle higher screen resolutions more effectively. (explain)

Radeon HD 5450		2600 Mpixels/sec
Radeon HD 4550 256MB		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: Bandwidth is the largest amount of information (measured in MB per second) that can be transferred across the external memory interface within a second. It's worked out by multiplying the card's bus width by its memory speed. If it uses DDR memory, the result should be multiplied by 2 again. If DDR5, multiply by 4 instead. The higher the bandwidth is, the better 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 applied in one second. This figure is calculated by multiplying the total amount of texture units by the core speed of the chip. The better this number, the better the video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied per second.

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