Radeon HD 4870 2GB vs Radeon HD 7750

Intro

Compare those specifications to the Radeon HD 7750, which has a core clock frequency of 800 MHz and a GDDR5 memory speed of 1125 MHz. It also features a 128-bit memory bus, and uses a 28 nm design. It features 512 SPUs, 32 TAUs, and 16 ROPs.

Display Graphs

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Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 7750		55 Watts
Radeon HD 4870 2GB		150 Watts
	Difference: 95 Watts (173%)

Memory Bandwidth

The Radeon HD 4870 2GB should theoretically be a lot faster than the Radeon HD 7750 in general. (explain)

Radeon HD 4870 2GB		115200 MB/sec
Radeon HD 7750		72000 MB/sec
	Difference: 43200 (60%)

Texel Rate

The Radeon HD 4870 2GB will be a bit (more or less 17%) more effective at texture filtering than the Radeon HD 7750. (explain)

Radeon HD 4870 2GB		30000 Mtexels/sec
Radeon HD 7750		25600 Mtexels/sec
	Difference: 4400 (17%)

Pixel Rate

The Radeon HD 7750 is just a bit (more or less 7%) more effective at anti-aliasing than the Radeon HD 4870 2GB, and also should be able to handle higher resolutions while still performing well. (explain)

Radeon HD 7750		12800 Mpixels/sec
Radeon HD 4870 2GB		12000 Mpixels/sec
	Difference: 800 (7%)

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 maximum amount of data (counted in megabytes per second) that can be transported over the external memory interface in one second. It is calculated by multiplying the interface width by its memory speed. If it uses DDR RAM, it must be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The higher the bandwidth is, 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 amount of texture map elements (texels) that are processed in one second. This figure is calculated by multiplying the total 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 handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in a second.

Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics card can possibly write to the local memory in one second - measured in millions of pixels per second. The number is calculated by multiplying the number of Render Output Units by the the card's clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel rate also depends on lots of other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to reach the maximum fill rate.