Radeon HD 3870 1GB vs Radeon HD 7750

Intro

Compare all of that to the Radeon HD 7750, which has a clock speed of 800 MHz and a GDDR5 memory speed of 1125 MHz. It also features a 128-bit memory bus, and makes use of a 28 nm design. It features 512 SPUs, 32 Texture Address Units, and 16 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 7750		55 Watts
Radeon HD 3870 1GB		106 Watts
	Difference: 51 Watts (93%)

Memory Bandwidth

Both cards have exactly the same bandwidth, so theoretically they should have identical performance. (explain)

Texel Rate

The Radeon HD 7750 is quite a bit (more or less 106%) better at AF than the Radeon HD 3870 1GB. (explain)

Radeon HD 7750		25600 Mtexels/sec
Radeon HD 3870 1GB		12400 Mtexels/sec
	Difference: 13200 (106%)

Pixel Rate

The Radeon HD 7750 will be a small bit (approximately 3%) more effective at FSAA than the Radeon HD 3870 1GB, and also will be able to handle higher screen resolutions without losing too much performance. (explain)

Radeon HD 7750		12800 Mpixels/sec
Radeon HD 3870 1GB		12400 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 max amount of data (measured in megabytes per second) that can be transported over the external memory interface within a second. It's calculated by multiplying the card's interface width by the speed of its memory. In the case of DDR memory, it should be multiplied by 2 again. If DDR5, multiply by 4 instead. The higher the card's memory bandwidth, the faster 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 texture map elements (texels) that are applied in one second. This number is worked out by multiplying the total number of texture units by the core speed of the chip. The better this number, the better the video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied per second.

Pixel Rate: Pixel rate is the most pixels that the graphics card can possibly record to the local memory in one second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number of colour ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel output rate also depends on quite a few other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the potential to get to the max fill rate.