Radeon HD 3870 X2 1GB vs Radeon R9 M265X

Intro

Compare those specifications to the Radeon R9 M265X, which comes with a GPU core clock speed of 575 MHz, and 2048 MB of GDDR5 RAM running at 1125 MHz through a 128-bit bus. It also features 640 SPUs, 40 TAUs, and 16 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

The Radeon HD 3870 X2 1GB, in theory, should perform much faster than the Radeon R9 M265X in general. (explain)

Radeon HD 3870 X2 1GB		144128 MB/sec
Radeon R9 M265X		72000 MB/sec
	Difference: 72128 (100%)

Texel Rate

The Radeon HD 3870 X2 1GB will be a little bit (more or less 15%) more effective at texture filtering than the Radeon R9 M265X. (explain)

Radeon HD 3870 X2 1GB		26400 Mtexels/sec
Radeon R9 M265X		23000 Mtexels/sec
	Difference: 3400 (15%)

Pixel Rate

The Radeon HD 3870 X2 1GB is quite a bit (approximately 187%) better at full screen anti-aliasing than the Radeon R9 M265X, and also should be able to handle higher resolutions more effectively. (explain)

Radeon HD 3870 X2 1GB		26400 Mpixels/sec
Radeon R9 M265X		9200 Mpixels/sec
	Difference: 17200 (187%)

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: Memory bandwidth is the maximum amount of information (measured in MB per second) that can be transferred over the external memory interface in one second. It is calculated by multiplying the bus width by its memory speed. If the card has DDR type memory, the result should be multiplied by 2 again. If DDR5, multiply by 4 instead. The higher the memory bandwidth, the faster the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.

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

Pixel Rate: Pixel rate is the maximum amount of pixels the graphics card could possibly write to the 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 clock speed of the card. ROPs (Raster Operations Pipelines - also sometimes called 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, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to get to the max fill rate.