Radeon HD 4870 1GB vs Radeon R9 M270X

Intro

Compare all that to the Radeon R9 M270X, which uses a 28 nm design. AMD has set the core speed at 725 MHz. The GDDR5 RAM works at a frequency of 1125 MHz on this specific card. It features 640 SPUs along with 40 Texture Address Units and 16 ROPs.

Display Graphs

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Power Usage and Theoretical Benchmarks

Memory Bandwidth

Performance-wise, the Radeon HD 4870 1GB should theoretically be much better than the Radeon R9 M270X overall. (explain)

Radeon HD 4870 1GB		115200 MB/sec
Radeon R9 M270X		72000 MB/sec
	Difference: 43200 (60%)

Texel Rate

The Radeon HD 4870 1GB will be a bit (about 3%) more effective at anisotropic filtering than the Radeon R9 M270X. (explain)

Radeon HD 4870 1GB		30000 Mtexels/sec
Radeon R9 M270X		29000 Mtexels/sec
	Difference: 1000 (3%)

Pixel Rate

The Radeon HD 4870 1GB will be a little bit (about 3%) better at FSAA than the Radeon R9 M270X, and should be able to handle higher screen resolutions better. (explain)

Radeon HD 4870 1GB		12000 Mpixels/sec
Radeon R9 M270X		11600 Mpixels/sec
	Difference: 400 (3%)

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 largest amount of information (in units of MB per second) that can be moved over the external memory interface in a second. It's calculated by multiplying the interface width by its memory speed. If it uses DDR RAM, the result should be multiplied by 2 once again. If DDR5, multiply by 4 instead. The higher the card's memory bandwidth, the faster the card will be in general. It especially helps with AA, HDR and high resolutions.

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

Pixel Rate: Pixel rate is the maximum number of pixels that the graphics card can possibly record to the local memory in one second - measured in millions of pixels per second. The figure is calculated by multiplying the amount of Render Output Units by the the core clock speed. 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 rate also depends on many other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to reach the maximum fill rate.