Radeon HD 3870 512MB vs Radeon R9 M265X

Intro

Compare all that to the Radeon R9 M265X, which uses a 28 nm design. AMD has clocked the core frequency at 575 MHz. The GDDR5 RAM runs at a frequency of 1125 MHz on this particular card. It features 640 SPUs as well as 40 Texture Address Units and 16 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

Performance-wise, the Radeon R9 M265X should in theory be quite a bit better than the Radeon HD 3870 512MB in general. (explain)

Radeon R9 M265X		72000 MB/sec
Radeon HD 3870 512MB		57600 MB/sec
	Difference: 14400 (25%)

Texel Rate

The Radeon R9 M265X will be quite a bit (about 85%) faster with regards to anisotropic filtering than the Radeon HD 3870 512MB. (explain)

Radeon R9 M265X		23000 Mtexels/sec
Radeon HD 3870 512MB		12400 Mtexels/sec
	Difference: 10600 (85%)

Pixel Rate

If using lots of anti-aliasing is important to you, then the Radeon HD 3870 512MB is the winner, by far. (explain)

Radeon HD 3870 512MB		12400 Mpixels/sec
Radeon R9 M265X		9200 Mpixels/sec
	Difference: 3200 (35%)

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 (measured in MB per second) that can be moved over the external memory interface in a second. The number is calculated by multiplying the bus width by its memory speed. If the card has DDR RAM, it should be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The higher the memory bandwidth, the faster the card will be in general. It especially helps with AA, HDR and higher screen resolutions.

Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are applied in one second. This is calculated by multiplying the total texture units by the core speed of the chip. The higher the texel rate, the better the graphics card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels in one second.

Pixel Rate: Pixel rate is the maximum number of pixels that the graphics card could possibly record to its local memory per second - measured in millions of pixels per second. The figure is calculated by multiplying the amount of Render Output Units by the clock 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 fill 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.