GeForce 9800 GTX vs Radeon HD 4850 X2 1GB

Intro

The GeForce 9800 GTX features a core clock frequency of 675 MHz and a GDDR3 memory speed of 1100 MHz. It also makes use of a 256-bit memory bus, and uses a 65 nm design. It is made up of 128 SPUs, 64 Texture Address Units, and 16 ROPs.

Compare all of that to the Radeon HD 4850 X2 1GB, which has a core clock frequency of 625 MHz and a GDDR3 memory speed of 993 MHz. It also uses a 256-bit memory bus, and uses a 55 nm design. It is comprised of 800(160x5) SPUs, 40 Texture Address Units, and 16 ROPs.

Price Comparison

Specifications

Memory Bandwidth: Bandwidth is the max amount of data (measured in MB per second) that can be moved past the external memory interface within a second. It is worked out by multiplying the bus width by the speed of its memory. If it uses DDR type memory, it must be multiplied by 2 once 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 higher screen resolutions.

Texel Rate: Texel rate is the maximum texture map elements (texels) that are applied in one second. This is worked out by multiplying the total number of texture units of the card by the core speed of the chip. The better this number, the better the graphics 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 maximum number of pixels the video 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 number of Render Output Units 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 output rate also depends on many other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the ability to get to the max fill rate.