Radeon HD 6870 vs Radeon HD 7770

Intro

Compare those specs to the Radeon HD 7770, which comes with a clock frequency of 1000 MHz and a GDDR5 memory frequency of 1125 MHz. It also uses a 128-bit bus, and uses a 28 nm design. It is comprised of 640 SPUs, 40 TAUs, and 16 ROPs.

Display Graphs

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Benchmarks

These are real-world performance benchmarks that were submitted by Hardware Compare users. The scores seen here are the average of all benchmarks submitted for each respective test and hardware.

3DMark Fire Strike Graphics Score

Radeon HD 7770		3180 points
Radeon HD 6870		2870 points
	Difference: 310 (11%)

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 7770		80 Watts
Radeon HD 6870		151 Watts
	Difference: 71 Watts (89%)

Memory Bandwidth

Performance-wise, the Radeon HD 6870 should theoretically be quite a bit better than the Radeon HD 7770 in general. (explain)

Radeon HD 6870		134400 MB/sec
Radeon HD 7770		72000 MB/sec
	Difference: 62400 (87%)

Texel Rate

The Radeon HD 6870 is quite a bit (approximately 26%) more effective at texture filtering than the Radeon HD 7770. (explain)

Radeon HD 6870		50400 Mtexels/sec
Radeon HD 7770		40000 Mtexels/sec
	Difference: 10400 (26%)

Pixel Rate

The Radeon HD 6870 should be much (approximately 80%) more effective at AA than the Radeon HD 7770, and capable of handling higher resolutions without losing too much performance. (explain)

Radeon HD 6870		28800 Mpixels/sec
Radeon HD 7770		16000 Mpixels/sec
	Difference: 12800 (80%)

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: Memory bandwidth is the largest amount of information (in units of MB per second) that can be transported past the external memory interface in a second. It is worked out by multiplying the bus width by its memory speed. If the card has DDR type memory, the result should be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The better the memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, HDR and higher screen resolutions.

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

Pixel Rate: Pixel rate is the maximum number of pixels the graphics card could possibly write to the local memory per second - measured in millions of pixels per second. The number is calculated by multiplying the amount of Render Output Units by the the core speed of the card. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel output rate is also dependant on lots of other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to reach the maximum fill rate.