Radeon HD 3850 256MB vs Radeon HD 4750

Intro

Compare that to the Radeon HD 4750, which has a core clock speed of 730 MHz and a GDDR5 memory speed of 800 MHz. It also makes use of a 128-bit memory bus, and makes use of a 40 nm design. It features 640(128x5) SPUs, 32 TAUs, and 16 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Both cards have the same power consumption.

Memory Bandwidth

Performance-wise, the Radeon HD 3850 256MB should in theory be a small bit better than the Radeon HD 4750 in general. (explain)

Radeon HD 3850 256MB		52992 MB/sec
Radeon HD 4750		51200 MB/sec
	Difference: 1792 (4%)

Texel Rate

The Radeon HD 4750 should be much (more or less 119%) faster with regards to anisotropic filtering than the Radeon HD 3850 256MB. (explain)

Radeon HD 4750		23360 Mtexels/sec
Radeon HD 3850 256MB		10688 Mtexels/sec
	Difference: 12672 (119%)

Pixel Rate

If using a high resolution is important to you, then the Radeon HD 4750 is the winner, though not by far. (explain)

Radeon HD 4750		11680 Mpixels/sec
Radeon HD 3850 256MB		10688 Mpixels/sec
	Difference: 992 (9%)

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 information (measured in megabytes per second) that can be moved over the external memory interface within a second. It's worked out by multiplying the interface width by its memory clock speed. If it uses DDR type memory, it should be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The better the memory bandwidth, the faster 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 per second. This figure is calculated by multiplying the total amount of texture units of the card by the core speed of the chip. The better the texel rate, the better the card will be at 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 the graphics card can possibly write to the local memory in a second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of ROPs by the clock speed of the card. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate also depends on quite a few other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the potential to reach the maximum fill rate.