Radeon HD 5850 vs Radeon HD 7770

Intro

Compare all of that to the Radeon HD 7770, which comes with a clock frequency of 1000 MHz and a GDDR5 memory frequency of 1125 MHz. It also makes use of a 128-bit memory bus, and uses a 28 nm design. It is comprised of 640 SPUs, 40 TAUs, and 16 Raster Operation Units.

Display Graphs

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Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 7770		80 Watts
Radeon HD 5850		151 Watts
	Difference: 71 Watts (89%)

Memory Bandwidth

Performance-wise, the Radeon HD 5850 should theoretically be quite a bit superior to the Radeon HD 7770 in general. (explain)

Radeon HD 5850		128000 MB/sec
Radeon HD 7770		72000 MB/sec
	Difference: 56000 (78%)

Texel Rate

The Radeon HD 5850 will be a lot (approximately 31%) faster with regards to anisotropic filtering than the Radeon HD 7770. (explain)

Radeon HD 5850		52200 Mtexels/sec
Radeon HD 7770		40000 Mtexels/sec
	Difference: 12200 (31%)

Pixel Rate

The Radeon HD 5850 should be much (about 45%) better at AA than the Radeon HD 7770, and also will be capable of handling higher screen resolutions without losing too much performance. (explain)

Radeon HD 5850		23200 Mpixels/sec
Radeon HD 7770		16000 Mpixels/sec
	Difference: 7200 (45%)

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 largest amount of data (in units of megabytes per second) that can be transferred over the external memory interface in a second. It is calculated by multiplying the card's bus width by its memory clock speed. If the card has DDR RAM, it must be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The better the card's memory bandwidth, the faster the card will be in general. It especially helps with AA, HDR and higher screen resolutions.

Texel Rate: Texel rate is the maximum texture map elements (texels) that are processed per second. This figure 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 graphics 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 number of pixels that the graphics chip could possibly write to the local memory in a second - measured in millions of pixels per second. The figure is worked out by multiplying the number of ROPs by the the card's clock speed. 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 lots of other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the ability to reach the maximum fill rate.