Radeon HD 4850 512MB vs Radeon HD 7870

Intro

Compare those specifications to the Radeon HD 7870, which comes with core speeds of 1000 MHz on the GPU, and 1200 MHz on the 2048 MB of GDDR5 memory. It features 1280 SPUs along with 80 Texture Address Units and 32 ROPs.

Display Graphs

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Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 4850 512MB		110 Watts
Radeon HD 7870		175 Watts
	Difference: 65 Watts (59%)

Memory Bandwidth

The Radeon HD 7870 should in theory be much faster than the Radeon HD 4850 512MB overall. (explain)

Radeon HD 7870		153600 MB/sec
Radeon HD 4850 512MB		63552 MB/sec
	Difference: 90048 (142%)

Texel Rate

The Radeon HD 7870 will be quite a bit (about 220%) more effective at texture filtering than the Radeon HD 4850 512MB. (explain)

Radeon HD 7870		80000 Mtexels/sec
Radeon HD 4850 512MB		25000 Mtexels/sec
	Difference: 55000 (220%)

Pixel Rate

The Radeon HD 7870 will be a lot (about 220%) better at anti-aliasing than the Radeon HD 4850 512MB, and also will be capable of handling higher screen resolutions better. (explain)

Radeon HD 7870		32000 Mpixels/sec
Radeon HD 4850 512MB		10000 Mpixels/sec
	Difference: 22000 (220%)

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 max amount of data (measured in megabytes per second) that can be transported across the external memory interface in a second. It's worked out by multiplying the card's bus width by its memory speed. In the case of DDR type RAM, the result should be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The higher the bandwidth is, the faster the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and higher screen resolutions.

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

Pixel Rate: Pixel rate is the most pixels the video card can possibly record to the local memory in one second - measured in millions of pixels per second. The number is worked out by multiplying the amount of colour ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel rate is also dependant on quite a few other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the potential to get to the maximum fill rate.