GeForce GTX 850M vs Radeon R7 250

Intro

The GeForce GTX 850M makes use of a 28 nm design. nVidia has clocked the core speed at 876 MHz. The DDR3 memory is set to run at a frequency of 1000 MHz on this specific card. It features 640 SPUs along with 40 Texture Address Units and 16 Rasterization Operator Units.

Compare that to the Radeon R7 250, which comes with a clock speed of 1000 MHz and a GDDR5 memory frequency of 1150 MHz. It also features a 128-bit memory bus, and uses a 28 nm design. It is made up of 384 SPUs, 24 Texture Address Units, and 8 ROPs.

Price Comparison

Specifications

Memory Bandwidth: Bandwidth is the largest amount of information (measured in MB per second) that can be moved across the external memory interface in one second. It's worked out by multiplying the bus width by its memory speed. If the card has DDR type RAM, it must be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The better the bandwidth is, the faster the card will be in general. It especially helps with AA, 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 worked out by multiplying the total amount of texture units of the card by the core speed of the chip. The higher the texel rate, the better the video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed per second.

Pixel Rate: Pixel rate is the maximum amount of pixels the video 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 colour ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel rate is also dependant on quite a few other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the ability to get to the max fill rate.