Radeon HD 4850 1GB vs Radeon HD 7850

Intro

Compare all that to the Radeon HD 7850, which features a core clock speed of 860 MHz and a GDDR5 memory frequency of 1200 MHz. It also makes use of a 256-bit memory bus, and makes use of a 28 nm design. It features 1024 SPUs, 64 Texture Address Units, and 32 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 4850 1GB		110 Watts
Radeon HD 7850		130 Watts
	Difference: 20 Watts (18%)

Memory Bandwidth

Theoretically, the Radeon HD 7850 should be quite a bit faster than the Radeon HD 4850 1GB in general. (explain)

Radeon HD 7850		153600 MB/sec
Radeon HD 4850 1GB		63552 MB/sec
	Difference: 90048 (142%)

Texel Rate

The Radeon HD 7850 is a lot (about 120%) better at anisotropic filtering than the Radeon HD 4850 1GB. (explain)

Radeon HD 7850		55040 Mtexels/sec
Radeon HD 4850 1GB		25000 Mtexels/sec
	Difference: 30040 (120%)

Pixel Rate

If using a high screen resolution is important to you, then the Radeon HD 7850 is superior to the Radeon HD 4850 1GB, by far. (explain)

Radeon HD 7850		27520 Mpixels/sec
Radeon HD 4850 1GB		10000 Mpixels/sec
	Difference: 17520 (175%)

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 information (counted in megabytes per second) that can be transported past the external memory interface in one second. The number is calculated by multiplying the card's bus width by the speed of its memory. If the card has DDR type memory, the result should be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The higher the card's memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and high resolutions.

Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are processed per second. This figure is calculated by multiplying the total number 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 one second.

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