Radeon HD 5550 vs Radeon HD 7770

Intro

Compare all that to the Radeon HD 7770, which comes with a clock speed of 1000 MHz and a GDDR5 memory speed of 1125 MHz. It also uses a 128-bit memory bus, and makes use of a 28 nm design. It features 640 SPUs, 40 Texture Address Units, and 16 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

The Radeon HD 7770, in theory, should perform a lot faster than the Radeon HD 5550 overall. (explain)

Radeon HD 7770		72000 MB/sec
Radeon HD 5550		12800 MB/sec
	Difference: 59200 (463%)

Texel Rate

The Radeon HD 7770 is a lot (more or less 355%) more effective at texture filtering than the Radeon HD 5550. (explain)

Radeon HD 7770		40000 Mtexels/sec
Radeon HD 5550		8800 Mtexels/sec
	Difference: 31200 (355%)

Pixel Rate

If running with high levels of AA is important to you, then the Radeon HD 7770 is a better choice, and very much so. (explain)

Radeon HD 7770		16000 Mpixels/sec
Radeon HD 5550		4400 Mpixels/sec
	Difference: 11600 (264%)

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 (counted in megabytes per second) that can be transferred across the external memory interface within a second. It's calculated by multiplying the card's interface width by its memory speed. If it uses DDR RAM, the result should be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The better the bandwidth is, the better the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.

Texel Rate: Texel rate is the maximum number of texture map elements (texels) that can be applied per second. This is calculated by multiplying the total number 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 processed in one second.

Pixel Rate: Pixel rate is the most pixels that the graphics chip could possibly record to its local memory in a second - measured in millions of pixels per second. Pixel rate 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 filling the screen with pixels (the image). The actual pixel fill rate also depends on quite a few other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the potential to get to the maximum fill rate.