Radeon HD 4870 2GB vs Radeon R9 M385X

Intro

Compare those specifications to the Radeon R9 M385X, which uses a 28 nm design. AMD has clocked the core speed at 1100 MHz. The GDDR5 memory is set to run at a frequency of 1500 MHz on this specific card. It features 896 SPUs as well as 56 TAUs and 16 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

Theoretically speaking, the Radeon HD 4870 2GB should perform just a bit faster than the Radeon R9 M385X in general. (explain)

Radeon HD 4870 2GB		115200 MB/sec
Radeon R9 M385X		96000 MB/sec
	Difference: 19200 (20%)

Texel Rate

The Radeon R9 M385X is much (about 105%) more effective at texture filtering than the Radeon HD 4870 2GB. (explain)

Radeon R9 M385X		61600 Mtexels/sec
Radeon HD 4870 2GB		30000 Mtexels/sec
	Difference: 31600 (105%)

Pixel Rate

The Radeon R9 M385X will be quite a bit (about 47%) more effective at anti-aliasing than the Radeon HD 4870 2GB, and also able to handle higher screen resolutions without slowing down too much. (explain)

Radeon R9 M385X		17600 Mpixels/sec
Radeon HD 4870 2GB		12000 Mpixels/sec
	Difference: 5600 (47%)

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 MB per second) that can be transferred across the external memory interface within a second. It is calculated by multiplying the card's interface width by its memory speed. In the case of DDR type memory, the result should be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The higher the 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 is worked out by multiplying the total texture units of the card by the core speed of the chip. The higher the texel rate, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels in a second.

Pixel Rate: Pixel rate is the maximum number of pixels the graphics card could possibly write to the local memory per second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number 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 output rate is also dependant on lots of other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to get to the maximum fill rate.