Compare any two graphics cards:
VS

Radeon HD 3870 X2 512MB vs Radeon HD 4870 512MB

Intro

The Radeon HD 3870 X2 512MB features a core clock speed of 825 MHz and a GDDR3 memory speed of 900 MHz. It also uses a 256-bit bus, and makes use of a 55 nm design. It is made up of 320(64x5) SPUs, 16 TAUs, and 16 ROPs.

Compare all that to the Radeon HD 4870 512MB, which has a GPU core clock speed of 750 MHz, and 512 MB of GDDR5 memory running at 900 MHz through a 256-bit bus. It also is comprised of 800(160x5) Stream Processors, 40 TAUs, and 16 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

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

Texel Rate

The Radeon HD 4870 512MB should be just a bit (about 14%) faster with regards to texture filtering than the Radeon HD 3870 X2 512MB. (explain)

Radeon HD 4870 512MB 30000 Mtexels/sec
Radeon HD 3870 X2 512MB 26400 Mtexels/sec
Difference: 3600 (14%)

Pixel Rate

If running with lots of anti-aliasing is important to you, then the Radeon HD 3870 X2 512MB is the winner, by a large margin. (explain)

Radeon HD 3870 X2 512MB 26400 Mpixels/sec
Radeon HD 4870 512MB 12000 Mpixels/sec
Difference: 14400 (120%)

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

Display Prices

Hide Prices

Radeon HD 3870 X2 512MB

Amazon.com

Check prices at:

Radeon HD 4870 512MB

Amazon.com

Check prices at:

Please note that the price comparisons are based on search keywords - sometimes it might show cards with very similar names that are not exactly the same as the one chosen in the comparison. We do try to filter out the wrong results as best we can, though.

Specifications

Display Specifications

Hide Specifications

Model Radeon HD 3870 X2 512MB Radeon HD 4870 512MB
Manufacturer AMD AMD
Year Jan 28, 2008 Jun 25, 2008
Code Name R680 RV770 XT
Memory 512 MB (x2) 512 MB
Core Speed 825 MHz (x2) 750 MHz
Memory Speed 1800 MHz (x2) 3600 MHz
Power (Max TDP) (Unknown) watts 150 watts
Bandwidth 115200 MB/sec 115200 MB/sec
Texel Rate 26400 Mtexels/sec 30000 Mtexels/sec
Pixel Rate 26400 Mpixels/sec 12000 Mpixels/sec
Unified Shaders 320(64x5) (x2) 800(160x5)
Texture Mapping Units 16 (x2) 40
Render Output Units 16 (x2) 16
Bus Type GDDR3 GDDR5
Bus Width 256-bit (x2) 256-bit
Fab Process 55 nm 55 nm
Transistors (Unknown) million 956 million
Bus PCIe 2.0 x16/(internal PCIe 1.1 x16) PCIe 2.0 x16
DirectX Version DirectX 10.1 DirectX 10.1
OpenGL Version OpenGL 3.0 OpenGL 3.0

Memory Bandwidth: Bandwidth is the maximum amount of data (counted in MB per second) that can be transported over the external memory interface within a second. It's calculated by multiplying the card's bus width by its memory speed. If it uses DDR RAM, it must be multiplied by 2 once again. If DDR5, multiply by 4 instead. The higher the bandwidth is, the better 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 can be processed in one second. This number is calculated by multiplying the total texture units of the card by the core clock speed of the chip. The better this number, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels per second.

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

Display Prices

Hide Prices

Radeon HD 3870 X2 512MB

Amazon.com

Check prices at:

Radeon HD 4870 512MB

Amazon.com

Check prices at:

Please note that the price comparisons are based on search keywords - sometimes it might show cards with very similar names that are not exactly the same as the one chosen in the comparison. We do try to filter out the wrong results as best we can, though.

Comments

Be the first to leave a comment!

Your email address will not be published. Required fields are marked *


*

WordPress Anti Spam by WP-SpamShield