Radeon HD 3870 X2 1GB vs Radeon R9 M395X

Intro

Compare that to the Radeon R9 M395X, which features a clock speed of 723 MHz and a GDDR5 memory frequency of 1250 MHz. It also uses a 256-bit memory bus, and makes use of a 28 nm design. It is comprised of 2048 SPUs, 128 Texture Address Units, and 32 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

Theoretically speaking, the Radeon R9 M395X should be 11% faster than the Radeon HD 3870 X2 1GB in general, due to its higher bandwidth. (explain)

Radeon R9 M395X		160000 MB/sec
Radeon HD 3870 X2 1GB		144128 MB/sec
	Difference: 15872 (11%)

Texel Rate

The Radeon R9 M395X should be much (about 251%) more effective at anisotropic filtering than the Radeon HD 3870 X2 1GB. (explain)

Radeon R9 M395X		92544 Mtexels/sec
Radeon HD 3870 X2 1GB		26400 Mtexels/sec
	Difference: 66144 (251%)

Pixel Rate

The Radeon HD 3870 X2 1GB will be a small bit (approximately 14%) more effective at AA than the Radeon R9 M395X, and also will be capable of handling higher screen resolutions without slowing down too much. (explain)

Radeon HD 3870 X2 1GB		26400 Mpixels/sec
Radeon R9 M395X		23136 Mpixels/sec
	Difference: 3264 (14%)

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.

One or more cards in this comparison are multi-core. This means that their bandwidth, texel and pixel rates are theoretically doubled - this does not mean the card will actually perform twice as fast, but only that it should in theory be able to. Actual game benchmarks will give a more accurate idea of what it's capable of.

Price Comparison

Specifications

Memory Bandwidth: Bandwidth is the largest amount of data (in units of megabytes per second) that can be transported over the external memory interface in a second. The number is worked out by multiplying the interface width by its memory speed. In the case of DDR type RAM, the result should be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The better the bandwidth is, the better the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and higher screen resolutions.

Texel Rate: Texel rate is the maximum texture map elements (texels) that can be processed in one second. This number is calculated by multiplying the total amount of texture units by the core clock speed of the chip. The better this number, the better the video 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 amount of pixels the graphics card can possibly write to its local memory in one second - measured in millions of pixels per second. The number is worked out by multiplying the number of colour ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - aka 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 potential to get to the max fill rate.