Radeon HD 4850 512MB vs Radeon HD 7770

Intro

Compare those specs to the Radeon HD 7770, which comes with core speeds of 1000 MHz on the GPU, and 1125 MHz on the 1024 MB of GDDR5 RAM. It features 640 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 7770		80 Watts
Radeon HD 4850 512MB		110 Watts
	Difference: 30 Watts (38%)

Memory Bandwidth

The Radeon HD 7770 should theoretically be a little bit faster than the Radeon HD 4850 512MB overall. (explain)

Radeon HD 7770		72000 MB/sec
Radeon HD 4850 512MB		63552 MB/sec
	Difference: 8448 (13%)

Texel Rate

The Radeon HD 7770 is quite a bit (about 60%) more effective at texture filtering than the Radeon HD 4850 512MB. (explain)

Radeon HD 7770		40000 Mtexels/sec
Radeon HD 4850 512MB		25000 Mtexels/sec
	Difference: 15000 (60%)

Pixel Rate

If using a high resolution is important to you, then the Radeon HD 7770 is a better choice, by a large margin. (explain)

Radeon HD 7770		16000 Mpixels/sec
Radeon HD 4850 512MB		10000 Mpixels/sec
	Difference: 6000 (60%)

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 data (in units of MB per second) that can be moved past the external memory interface in a second. The number is worked out by multiplying the interface width by the speed of its memory. If it uses DDR memory, the result should be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The better the card's memory bandwidth, the better the card will be in general. It especially helps with AA, HDR and higher screen resolutions.

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

Pixel Rate: Pixel rate is the most pixels that the graphics card could possibly record to the local memory in a second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the number of Render Output Units by the the core speed of the card. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate also depends on quite a few other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the potential to get to the max fill rate.