Radeon HD 4870 1GB vs Radeon HD 5450

Intro

Compare those specifications to the Radeon HD 5450, which comes with a GPU core clock speed of 650 MHz, and 512 MB of DDR3 memory set to run at 800 MHz through a 64-bit bus. It also is comprised of 80(16x5) SPUs, 8 Texture Address Units, and 4 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 5450		19 Watts
Radeon HD 4870 1GB		150 Watts
	Difference: 131 Watts (689%)

Memory Bandwidth

As far as performance goes, the Radeon HD 4870 1GB should in theory be a lot better than the Radeon HD 5450 in general. (explain)

Radeon HD 4870 1GB		115200 MB/sec
Radeon HD 5450		12800 MB/sec
	Difference: 102400 (800%)

Texel Rate

The Radeon HD 4870 1GB will be quite a bit (approximately 477%) faster with regards to texture filtering than the Radeon HD 5450. (explain)

Radeon HD 4870 1GB		30000 Mtexels/sec
Radeon HD 5450		5200 Mtexels/sec
	Difference: 24800 (477%)

Pixel Rate

If using a high screen resolution is important to you, then the Radeon HD 4870 1GB is superior to the Radeon HD 5450, by a large margin. (explain)

Radeon HD 4870 1GB		12000 Mpixels/sec
Radeon HD 5450		2600 Mpixels/sec
	Difference: 9400 (362%)

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 data (counted in megabytes per second) that can be moved past the external memory interface within a second. The number is worked out by multiplying the interface width by the speed of its memory. In the case of DDR type memory, it must be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The better the card's memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and higher screen resolutions.

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

Pixel Rate: Pixel rate is the most pixels the graphics card can possibly record 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 the card's clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel output rate also depends on lots of other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the potential to get to the max fill rate.