Radeon HD 4870 2GB vs Radeon R9 M385X

Intro

Compare those specs to the Radeon R9 M385X, which has a clock frequency of 1100 MHz and a GDDR5 memory frequency of 1500 MHz. It also uses a 128-bit memory bus, and uses a 28 nm design. It is made up of 896 SPUs, 56 TAUs, and 16 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

As far as performance goes, the Radeon HD 4870 2GB should theoretically be a small bit better 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 (approximately 105%) better 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 is much (approximately 47%) better at full screen anti-aliasing than the Radeon HD 4870 2GB, and capable of handling higher resolutions more effectively. (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 maximum amount of data (in units of MB per second) that can be moved past the external memory interface within a second. It is calculated by multiplying the card's bus width by the speed of its memory. If the card has DDR type memory, it must be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The higher the card's 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 amount of texture map elements (texels) that can be applied per second. This figure is worked out by multiplying the total number of texture units 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 per second.

Pixel Rate: Pixel rate is the most pixels the graphics card can possibly write to its local memory per second - measured in millions of pixels per second. The number is worked out by multiplying the number of Raster Operations Pipelines by the the core speed of the card. ROPs (Raster Operations Pipelines - aka 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, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to reach the maximum fill rate.