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Radeon HD 4870 1GB vs Radeon HD 4890 2GB
Intro
The Radeon HD 4870 1GB features a core clock frequency of 750 MHz and a GDDR5 memory frequency of 900 MHz. It also uses a 256-bit bus, and uses a 55 nm design. It features 800(160x5) SPUs, 40 TAUs, and 16 Raster Operation Units.Compare those specs to the Radeon HD 4890 2GB, which makes use of a 55 nm design. AMD has set the core speed at 1000 MHz. The GDDR5 RAM runs at a frequency of 975 MHz on this specific card. It features 800(160x5) SPUs along with 40 Texture Address Units and 16 Rasterization Operator 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
In theory, the Radeon HD 4890 2GB is 8% faster than the Radeon HD 4870 1GB overall, due to its higher data rate. (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 is quite a bit (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 running with lots of anti-aliasing is important to you, then the Radeon HD 4890 2GB is a better choice, and very much so. (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 max amount of data (measured in megabytes per second) that can be moved across the external memory interface in a second. The number is calculated by multiplying the card's bus width by the speed of its memory. If the card has DDR type RAM, it must be multiplied by 2 again. If DDR5, multiply by 4 instead. The better the card's memory bandwidth, the faster the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be processed per second. This is worked out by multiplying the total number of texture units of the card by the core speed of the chip. The higher 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 most pixels the graphics card could possibly write to its local memory per second - measured in millions of pixels per second. The number is worked out by multiplying the number of colour ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel rate also depends on many other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the potential to get to 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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