Radeon HD 4850 512MB vs Radeon HD 6770

Intro

Compare those specifications to the Radeon HD 6770, which features core clock speeds of 900 MHz on the GPU, and 1050 MHz on the 512 MB of GDDR5 RAM. It features 800 SPUs as well as 40 Texture Address Units and 16 ROPs.

Display Graphs

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Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 6770		108 Watts
Radeon HD 4850 512MB		110 Watts
	Difference: 2 Watts (2%)

Memory Bandwidth

The Radeon HD 6770, in theory, should perform a small bit faster than the Radeon HD 4850 512MB in general. (explain)

Radeon HD 6770		67200 MB/sec
Radeon HD 4850 512MB		63552 MB/sec
	Difference: 3648 (6%)

Texel Rate

The Radeon HD 6770 will be quite a bit (about 44%) faster with regards to AF than the Radeon HD 4850 512MB. (explain)

Radeon HD 6770		36000 Mtexels/sec
Radeon HD 4850 512MB		25000 Mtexels/sec
	Difference: 11000 (44%)

Pixel Rate

The Radeon HD 6770 is much (approximately 44%) more effective at AA than the Radeon HD 4850 512MB, and also should be capable of handling higher screen resolutions without losing too much performance. (explain)

Radeon HD 6770		14400 Mpixels/sec
Radeon HD 4850 512MB		10000 Mpixels/sec
	Difference: 4400 (44%)

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 maximum amount of information (in units of MB per second) that can be moved over the external memory interface in a second. It's worked out by multiplying the bus width by its memory speed. If the card has DDR type RAM, it must be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The higher the bandwidth is, 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 texture map elements (texels) that can be processed per second. This number is calculated by multiplying the total amount of texture units by the core clock 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 that the graphics card can possibly record to the local memory in one second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of Render Output Units by the the core speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel rate is also dependant on quite a few other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to get to the max fill rate.