Radeon HD 4750 vs Radeon HD 7770

Intro

Compare those specs to the Radeon HD 7770, which has core clock 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 4750		75 Watts
Radeon HD 7770		80 Watts
	Difference: 5 Watts (7%)

Memory Bandwidth

Theoretically speaking, the Radeon HD 7770 should be 41% faster than the Radeon HD 4750 overall, due to its greater data rate. (explain)

Radeon HD 7770		72000 MB/sec
Radeon HD 4750		51200 MB/sec
	Difference: 20800 (41%)

Texel Rate

The Radeon HD 7770 will be a lot (more or less 71%) better at anisotropic filtering than the Radeon HD 4750. (explain)

Radeon HD 7770		40000 Mtexels/sec
Radeon HD 4750		23360 Mtexels/sec
	Difference: 16640 (71%)

Pixel Rate

If running with high levels of AA is important to you, then the Radeon HD 7770 is superior to the Radeon HD 4750, by far. (explain)

Radeon HD 7770		16000 Mpixels/sec
Radeon HD 4750		11680 Mpixels/sec
	Difference: 4320 (37%)

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 max amount of information (measured in megabytes per second) that can be moved across the external memory interface within a second. The number is worked out by multiplying the bus width by its memory clock speed. In the case of DDR memory, it should be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The higher the card's memory bandwidth, 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 amount of texture map elements (texels) that are applied in one second. This number is calculated by multiplying the total number of texture units by the core clock speed of the chip. The better the texel rate, the better the graphics card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels per second.

Pixel Rate: Pixel rate is the maximum amount of pixels the graphics card could possibly record to the local memory in one second - measured in millions of pixels per second. The figure is calculated by multiplying the number of ROPs by the clock 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, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to get to the max fill rate.