Radeon HD 4870 2GB vs Radeon R9 M385X

Intro

Compare all of that to the Radeon R9 M385X, which uses a 28 nm design. AMD has clocked the core frequency at 1100 MHz. The GDDR5 RAM runs at a speed of 1500 MHz on this specific model. It features 896 SPUs as well as 56 Texture Address Units and 16 Rasterization Operator Units.

Display Graphs

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Power Usage and Theoretical Benchmarks

Memory Bandwidth

As far as performance goes, the Radeon HD 4870 2GB should theoretically be just a bit superior to the Radeon R9 M385X overall. (explain)

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

Texel Rate

The Radeon R9 M385X will be a lot (approximately 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 is much (approximately 47%) faster with regards to FSAA than the Radeon HD 4870 2GB, and will be capable of handling higher screen 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: Bandwidth is the max amount of information (in units of megabytes per second) that can be transferred over the external memory interface in one second. It is worked out by multiplying the interface width by its memory speed. If it uses DDR RAM, it should be multiplied by 2 once again. If 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 higher screen 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 texture units of the card by the core speed of the chip. The better this number, the better the graphics card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels in a second.

Pixel Rate: Pixel rate is the most pixels the graphics card could possibly write to its local memory in a second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the amount of ROPs by the clock speed of the card. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel fill rate is also dependant on many other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to get to the max fill rate.