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Radeon HD 4870 1GB vs Radeon HD 4890 2GB
Intro
The Radeon HD 4870 1GB features a clock frequency of 750 MHz and a GDDR5 memory frequency of 900 MHz. It also makes use of a 256-bit bus, and makes use of a 55 nm design. It features 800(160x5) SPUs, 40 Texture Address Units, and 16 Raster Operation Units.Compare those specifications to the Radeon HD 4890 2GB, which has GPU core speed of 1000 MHz, and 2048 MB of GDDR5 RAM set to run at 975 MHz through a 256-bit bus. It also is made up of 800(160x5) SPUs, 40 TAUs, and 16 Raster Operation Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
| Radeon HD 4870 1GB |
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150 Watts |
| Radeon HD 4890 2GB |
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190 Watts |
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Memory Bandwidth
Theoretically, the Radeon HD 4890 2GB should be a small bit faster than the Radeon HD 4870 1GB overall. (explain)
| Radeon HD 4890 2GB |
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124800 MB/sec |
| Radeon HD 4870 1GB |
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115200 MB/sec |
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Texel Rate
The Radeon HD 4890 2GB should be a lot (about 33%) better at anisotropic filtering than the Radeon HD 4870 1GB. (explain)| Radeon HD 4890 2GB |
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40000 Mtexels/sec |
| Radeon HD 4870 1GB |
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30000 Mtexels/sec |
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Pixel Rate
If using lots of anti-aliasing is important to you, then the Radeon HD 4890 2GB is the winner, by a large margin. (explain)| Radeon HD 4890 2GB |
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16000 Mpixels/sec |
| Radeon HD 4870 1GB |
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12000 Mpixels/sec |
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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
Radeon HD 4870 1GBAmazon.com
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Radeon HD 4890 2GBAmazon.com
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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
| Model | Radeon HD 4870 1GB | Radeon HD 4890 2GB |
|---|---|---|
| Manufacturer | AMD | AMD |
| Year | Jun 25, 2008 | Apr 2, 2009 |
| Code Name | RV770 XT | RV790 XT |
| Memory | 1024 MB | 2048 MB |
| Core Speed | 750 MHz | 1000 MHz |
| Memory Speed | 3600 MHz | 3900 MHz |
| Power (Max TDP) | 150 watts | 190 watts |
| Bandwidth | 115200 MB/sec | 124800 MB/sec |
| Texel Rate | 30000 Mtexels/sec | 40000 Mtexels/sec |
| Pixel Rate | 12000 Mpixels/sec | 16000 Mpixels/sec |
| Unified Shaders | 800(160x5) | 800(160x5) |
| Texture Mapping Units | 40 | 40 |
| Render Output Units | 16 | 16 |
| Bus Type | GDDR5 | GDDR5 |
| Bus Width | 256-bit | 256-bit |
| Fab Process | 55 nm | 55 nm |
| Transistors | 956 million | 959 million |
| Bus | PCIe 2.0 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 largest amount of data (counted in megabytes per second) that can be transferred past the external memory interface within a second. It is worked out by multiplying the card's bus width by its memory clock speed. If the card has DDR RAM, it must be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The better the bandwidth is, the better the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and higher screen resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that are applied per second. This is calculated by multiplying the total texture units of the card by the core 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 applied in a second.
Pixel Rate: Pixel rate is the maximum number of pixels that the graphics card can possibly record to its local memory in a second - measured in millions of pixels per second. The number is calculated by multiplying the amount of Raster Operations Pipelines by the clock speed of the card. ROPs (Raster Operations Pipelines - also sometimes 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, especially the memory bandwidth - the lower the memory bandwidth is, the lower the potential to reach the max fill rate.
Radeon HD 4870 1GBAmazon.com
Check prices at:
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Radeon HD 4890 2GBAmazon.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.
|
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