Radeon HD 4650 512MB vs Radeon R5 M255

Intro

Compare those specs to the Radeon R5 M255, which uses a 28 nm design. AMD has clocked the core frequency at 940 MHz. The DDR3 RAM runs at a frequency of 1000 MHz on this specific model. It features 320 SPUs as well as 20 Texture Address Units and 8 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

Both cards have exactly the same memory bandwidth, so in theory they should have the same performance. (explain)

Texel Rate

The Radeon HD 4650 512MB should be just a bit (more or less 2%) better at texture filtering than the Radeon R5 M255. (explain)

Radeon HD 4650 512MB		19200 Mtexels/sec
Radeon R5 M255		18800 Mtexels/sec
	Difference: 400 (2%)

Pixel Rate

If using a high screen resolution is important to you, then the Radeon R5 M255 is the winner, by a large margin. (explain)

Radeon R5 M255		7520 Mpixels/sec
Radeon HD 4650 512MB		4800 Mpixels/sec
	Difference: 2720 (57%)

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 data (counted in megabytes per second) that can be moved over the external memory interface in one second. The number is worked out by multiplying the card's interface width by the speed of its memory. If the card has DDR RAM, it must be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The better the card's memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, HDR and high resolutions.

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

Pixel Rate: Pixel rate is the most pixels the graphics card can possibly record to the local memory in one second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the amount of Raster Operations Pipelines by the the card's clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel output rate is also dependant on quite a few other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to reach the maximum fill rate.