Radeon HD 4890 2GB vs Radeon HD 6450 (OEM) 1GB

Intro

Compare those specs to the Radeon HD 6450 (OEM) 1GB, which uses a 40 nm design. AMD has clocked the core frequency at 750 MHz. The GDDR5 memory works at a frequency of 900 MHz on this model. It features 160 SPUs as well as 8 TAUs and 4 ROPs.

Display Graphs

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Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 6450 (OEM) 1GB		31 Watts
Radeon HD 4890 2GB		190 Watts
	Difference: 159 Watts (513%)

Memory Bandwidth

Theoretically, the Radeon HD 4890 2GB should perform quite a bit faster than the Radeon HD 6450 (OEM) 1GB in general. (explain)

Radeon HD 4890 2GB		124800 MB/sec
Radeon HD 6450 (OEM) 1GB		28800 MB/sec
	Difference: 96000 (333%)

Texel Rate

The Radeon HD 4890 2GB will be much (approximately 567%) more effective at texture filtering than the Radeon HD 6450 (OEM) 1GB. (explain)

Radeon HD 4890 2GB		40000 Mtexels/sec
Radeon HD 6450 (OEM) 1GB		6000 Mtexels/sec
	Difference: 34000 (567%)

Pixel Rate

If using high levels of AA is important to you, then the Radeon HD 4890 2GB is the winner, by a large margin. (explain)

Radeon HD 4890 2GB		16000 Mpixels/sec
Radeon HD 6450 (OEM) 1GB		3000 Mpixels/sec
	Difference: 13000 (433%)

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 largest amount of data (counted in megabytes per second) that can be moved past the external memory interface in a second. It is calculated by multiplying the interface width by its memory speed. If it uses DDR memory, it should be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The higher 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 texture map elements (texels) that are applied in one second. This number is worked out by multiplying the total amount of texture units of the card by the core clock speed of the chip. The better this number, the better the video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in one second.

Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics chip could possibly record to the local memory per second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the amount of colour ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel fill rate is also dependant on quite a few other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the ability to get to the max fill rate.