Radeon HD 4550 256MB vs Radeon HD 5550

Intro

Compare that to the Radeon HD 5550, which features core clock speeds of 550 MHz on the GPU, and 400 MHz on the 512 MB of DDR2 RAM. It features 320(64x5) SPUs along with 16 Texture Address Units and 8 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

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

Texel Rate

The Radeon HD 5550 is much (about 83%) more effective at texture filtering than the Radeon HD 4550 256MB. (explain)

Radeon HD 5550		8800 Mtexels/sec
Radeon HD 4550 256MB		4800 Mtexels/sec
	Difference: 4000 (83%)

Pixel Rate

If using lots of anti-aliasing is important to you, then the Radeon HD 5550 is the winner, by a large margin. (explain)

Radeon HD 5550		4400 Mpixels/sec
Radeon HD 4550 256MB		2400 Mpixels/sec
	Difference: 2000 (83%)

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 information (measured in megabytes per second) that can be transported over the external memory interface within a second. It is worked out by multiplying the card's interface width by its memory clock speed. In the case of DDR type memory, it should be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The better the memory bandwidth, the faster the card will be in general. It especially helps with AA, High Dynamic Range and higher screen resolutions.

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

Pixel Rate: Pixel rate is the most pixels the graphics card could possibly record to the local memory in one second - measured in millions of pixels per second. The figure is calculated by multiplying the amount of colour 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 also depends on quite a few other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the ability to get to the maximum fill rate.