Radeon HD 4870 512MB vs Radeon HD 6750 1GB

Intro

Compare that to the Radeon HD 6750 1GB, which features a GPU core clock speed of 725 MHz, and 1024 MB of GDDR5 RAM set to run at 1000 MHz through a 128-bit bus. It also is made up of 720 Stream Processors, 36 TAUs, and 16 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 6750 1GB		86 Watts
Radeon HD 4870 512MB		150 Watts
	Difference: 64 Watts (74%)

Memory Bandwidth

As far as performance goes, the Radeon HD 4870 512MB should theoretically be a lot superior to the Radeon HD 6750 1GB overall. (explain)

Radeon HD 4870 512MB		115200 MB/sec
Radeon HD 6750 1GB		64000 MB/sec
	Difference: 51200 (80%)

Texel Rate

The Radeon HD 4870 512MB is a little bit (approximately 15%) faster with regards to anisotropic filtering than the Radeon HD 6750 1GB. (explain)

Radeon HD 4870 512MB		30000 Mtexels/sec
Radeon HD 6750 1GB		26100 Mtexels/sec
	Difference: 3900 (15%)

Pixel Rate

The Radeon HD 4870 512MB should be a bit (approximately 3%) better at AA than the Radeon HD 6750 1GB, and should be capable of handling higher screen resolutions while still performing well. (explain)

Radeon HD 4870 512MB		12000 Mpixels/sec
Radeon HD 6750 1GB		11600 Mpixels/sec
	Difference: 400 (3%)

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 largest amount of data (in units of MB per second) that can be transferred over the external memory interface in a second. It's worked out by multiplying the card's interface width by the speed of its memory. If the card has DDR type RAM, it must be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The higher the memory bandwidth, the better the card will be in general. It especially helps with AA, HDR and high resolutions.

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

Pixel Rate: Pixel rate is the maximum number of pixels that the graphics chip can possibly record to its local memory in a second - measured in millions of pixels per second. The number is worked out by multiplying the amount of ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for outputting the pixels (image) to the screen. 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 ability to reach the max fill rate.