Radeon HD 3870 1GB vs Radeon R9 M385X

Intro

Compare all of that to the Radeon R9 M385X, which has GPU clock speed of 1100 MHz, and 4096 MB of GDDR5 memory set to run at 1500 MHz through a 128-bit bus. It also features 896 SPUs, 56 Texture Address Units, and 16 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

Performance-wise, the Radeon R9 M385X should in theory be a lot superior to the Radeon HD 3870 1GB overall. (explain)

Radeon R9 M385X		96000 MB/sec
Radeon HD 3870 1GB		72000 MB/sec
	Difference: 24000 (33%)

Texel Rate

The Radeon R9 M385X is much (about 397%) better at anisotropic filtering than the Radeon HD 3870 1GB. (explain)

Radeon R9 M385X		61600 Mtexels/sec
Radeon HD 3870 1GB		12400 Mtexels/sec
	Difference: 49200 (397%)

Pixel Rate

If running with high levels of AA is important to you, then the Radeon R9 M385X is a better choice, and very much so. (explain)

Radeon R9 M385X		17600 Mpixels/sec
Radeon HD 3870 1GB		12400 Mpixels/sec
	Difference: 5200 (42%)

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 maximum amount of information (in units of MB per second) that can be transported over the external memory interface within a second. It is worked out by multiplying the bus width by its memory clock speed. If the card has DDR memory, it should be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The better the card's memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, HDR and high resolutions.

Texel Rate: Texel rate is the maximum texture map elements (texels) that are applied per second. This figure is calculated by multiplying the total amount of texture units by the core clock 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 the graphics card can possibly record to the local memory per second - measured in millions of pixels per second. The number is calculated by multiplying the number of colour ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel output rate is also dependant on many other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the ability to get to the maximum fill rate.