Radeon HD 4550 512MB vs Radeon HD 6770

Intro

Compare all that to the Radeon HD 6770, which features GPU clock speed of 900 MHz, and 512 MB of GDDR5 memory set to run at 1050 MHz through a 128-bit bus. It also is comprised of 800 Stream Processors, 40 TAUs, and 16 Raster Operation Units.

Display Graphs

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Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 4550 512MB		25 Watts
Radeon HD 6770		108 Watts
	Difference: 83 Watts (332%)

Memory Bandwidth

The Radeon HD 6770 should theoretically be much faster than the Radeon HD 4550 512MB in general. (explain)

Radeon HD 6770		67200 MB/sec
Radeon HD 4550 512MB		12800 MB/sec
	Difference: 54400 (425%)

Texel Rate

The Radeon HD 6770 should be quite a bit (about 650%) faster with regards to AF than the Radeon HD 4550 512MB. (explain)

Radeon HD 6770		36000 Mtexels/sec
Radeon HD 4550 512MB		4800 Mtexels/sec
	Difference: 31200 (650%)

Pixel Rate

The Radeon HD 6770 will be a lot (approximately 500%) better at full screen anti-aliasing than the Radeon HD 4550 512MB, and also capable of handling higher screen resolutions while still performing well. (explain)

Radeon HD 6770		14400 Mpixels/sec
Radeon HD 4550 512MB		2400 Mpixels/sec
	Difference: 12000 (500%)

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 (in units of MB per second) that can be transported across the external memory interface within a second. It is calculated by multiplying the bus width by the speed of its memory. If it uses DDR type RAM, it should be multiplied by 2 again. If DDR5, multiply by 4 instead. The higher 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 texture map elements (texels) that are processed per second. This figure is calculated by multiplying the total number of texture units by the core speed of the chip. The better the texel rate, the better the 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 write to the local memory per second - measured in millions of pixels per second. The figure is worked out by multiplying the number of ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel fill rate is also dependant on many other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to get to the maximum fill rate.