Radeon HD 3870 X2 1GB vs Radeon HD 4850 1GB

Intro

Compare all of that to the Radeon HD 4850 1GB, which features a core clock frequency of 625 MHz and a GDDR4 memory frequency of 993 MHz. It also features a 256-bit memory bus, and uses a 55 nm design. It features 800(160x5) SPUs, 40 Texture Address Units, and 16 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

Theoretically speaking, the Radeon HD 3870 X2 1GB should be a lot faster than the Radeon HD 4850 1GB in general. (explain)

Radeon HD 3870 X2 1GB		144128 MB/sec
Radeon HD 4850 1GB		63552 MB/sec
	Difference: 80576 (127%)

Texel Rate

The Radeon HD 3870 X2 1GB is just a bit (approximately 6%) more effective at texture filtering than the Radeon HD 4850 1GB. (explain)

Radeon HD 3870 X2 1GB		26400 Mtexels/sec
Radeon HD 4850 1GB		25000 Mtexels/sec
	Difference: 1400 (6%)

Pixel Rate

If using high levels of AA is important to you, then the Radeon HD 3870 X2 1GB is superior to the Radeon HD 4850 1GB, and very much so. (explain)

Radeon HD 3870 X2 1GB		26400 Mpixels/sec
Radeon HD 4850 1GB		10000 Mpixels/sec
	Difference: 16400 (164%)

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.

One or more cards in this comparison are multi-core. This means that their bandwidth, texel and pixel rates are theoretically doubled - this does not mean the card will actually perform twice as fast, but only that it should in theory be able to. Actual game benchmarks will give a more accurate idea of what it's capable of.

Price Comparison

Specifications

Memory Bandwidth: Memory bandwidth is the maximum amount of information (measured in MB per second) that can be transported across the external memory interface in one second. It's worked out by multiplying the bus width by the speed of its memory. In the case of DDR type memory, it should be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The better the card's memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, HDR and higher screen resolutions.

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

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