Radeon HD 4550 256MB vs Radeon HD 6450 (OEM)

Intro

Compare those specs to the Radeon HD 6450 (OEM), which features GPU clock speed of 625 MHz, and 512 MB of GDDR3 memory set to run at 800 MHz through a 64-bit bus. It also is made up of 160 SPUs, 8 Texture Address Units, and 4 ROPs.

Display Graphs

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Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 4550 256MB		25 Watts
Radeon HD 6450 (OEM)		31 Watts
	Difference: 6 Watts (24%)

Memory Bandwidth

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

Texel Rate

The Radeon HD 6450 (OEM) should be a small bit (more or less 4%) faster with regards to texture filtering than the Radeon HD 4550 256MB. (explain)

Radeon HD 6450 (OEM)		5000 Mtexels/sec
Radeon HD 4550 256MB		4800 Mtexels/sec
	Difference: 200 (4%)

Pixel Rate

The Radeon HD 6450 (OEM) will be just a bit (about 4%) more effective at anti-aliasing than the Radeon HD 4550 256MB, and will be able to handle higher screen resolutions without losing too much performance. (explain)

Radeon HD 6450 (OEM)		2500 Mpixels/sec
Radeon HD 4550 256MB		2400 Mpixels/sec
	Difference: 100 (4%)

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 data (counted in MB per second) that can be moved past the external memory interface within a second. The number is calculated by multiplying the card's bus width by its memory speed. If it uses DDR type memory, it must be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The higher the card's memory bandwidth, the better 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 amount of texture map elements (texels) that are applied in one second. This number is calculated by multiplying the total number of texture units by the core speed of the chip. The better this number, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in a second.

Pixel Rate: Pixel rate is the maximum amount of pixels the video card can possibly write to its local memory in a second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the amount of Render Output Units by the the card's clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate is also dependant on many other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to reach the maximum fill rate.