Architecture Overview
TeraScale is the VLIW5 (Very Long Instruction Word, 5-wide) shader architecture used across ATI and AMD discrete GPUs from 2007 through 2010, spanning the Radeon HD 2000, 3000, and 4000 series. It succeeded the R580/R600 design and represented ATI's first DirectX 10 GPU family. The RV770 die (Radeon HD 4870) was a landmark product: a 55nm design that delivered strong performance at a competitive price and forced NVIDIA to cut prices on its GeForce GTX 200 series.
Quick Facts
- Architecture name
- TeraScale (VLIW5)
- Launch era / years active
- 2007 to 2010
- Predecessor
- R580 / Xenos (Xbox 360)
- Successor
- TeraScale 2
- Process nodes
- 80nm (R600), 65nm (RV670), 55nm (RV770)
- Important chips
- R600 (HD 2900 XT), RV670 (HD 3870 / 3850), RV770 (HD 4870 / 4850), RV730 (HD 4670), RV710 (HD 4350)
- Memory technologies
- GDDR3 (early), GDDR4 (R600 / HD 2900 XT), GDDR5 (HD 4870)
- CUDA / RT / Tensor generation
- VLIW5 Stream Processors; DirectX 10 (R600/RV670), DirectX 10.1 (RV770 and later); OpenCL 1.0 (late models)
- Consumer series
- Radeon HD 2900 series, HD 3800 / 3600 / 3400 series, HD 4800 / 4600 / 4500 / 4300 series
- Workstation / professional series
- ATI FirePro V8700, V7750 (RV770-based)
- Data center series
- ATI FireStream 9250 (RV770-based compute card)
- Source review status
- Source review complete for primary consumer product line.
What this architecture changed
VLIW5 shader array: each shader processor cluster handles a 5-wide VLIW instruction bundle, requiring the compiler to pack instructions efficiently.
First ATI architecture with DirectX 10 compliance (R600), and first with DirectX 10.1 (RV770).
GDDR5 debut on a consumer GPU: HD 4870 was the first shipping consumer card with GDDR5 memory (256-bit at 115.2 GB/s).
HD 4870 X2: dual-GPU card on a single PCB, an early AMD dual-GPU reference design.
Stream computing (ATI Stream): early OpenCL-precursor compute support on select models.
Why it mattered
The TeraScale HD 4870 and HD 4850 are remembered as the GPUs that re-established ATI as a competitive force at the mainstream and high-end segments. The RV770 in particular forced aggressive NVIDIA price cuts and set a precedent for AMD using aggressive pricing and competitive architecture to pressure the market. The HD 4870's GDDR5 adoption was a key industry moment, making GDDR5 the dominant GPU memory standard for the following decade.
Related GPUs
Popular GPU entries
| GPU | Architecture | Launch Date | Shader Processors | Memory | Bus Width | TDP/TBP | Segment |
|---|---|---|---|---|---|---|---|
| Mobility Radeon HD 4670 Mac Edition | TeraScale | 2009-09-16 | 320 | 256 MB GDDR3 | 128-bit | 35 W | Mobile |
| Mobility Radeon HD 4350 | TeraScale | 2009-01-09 | 80 | 512 MB GDDR3 | 64-bit | — | Mobile |
| Mobility Radeon HD 4850 Mac Edition | TeraScale | 2009-08-28 | 800 | 512 MB GDDR3 | 256-bit | — | Mobile |
| Mobility Radeon HD 4830 | TeraScale | 2009-03-03 | 640 | 1 GB GDDR3 | 128-bit | — | Mobile |
| Mobility Radeon HD 4860 | TeraScale | 2009-03-03 | 640 | 1 GB GDDR5 | 128-bit | — | Mobile |
| Mobility Radeon HD 4530 | TeraScale | 2009-01-09 | 80 | 512 MB GDDR3 | 64-bit | — | Mobile |
| Mobility Radeon HD 4570 | TeraScale | 2009-01-09 | 80 | 512 MB GDDR3 | 64-bit | — | Mobile |
| Mobility Radeon HD 4650 | TeraScale | 2009-01-09 | 320 | 1 GB GDDR3 | 128-bit | 35 W | Mobile |
| Mobility Radeon HD 4670 | TeraScale | 2009-01-09 | 320 | 512 MB GDDR3 | 128-bit | 35 W | Mobile |
| Mobility Radeon HD 4850 | TeraScale | 2009-01-09 | 800 | 1 GB GDDR3 | 256-bit | — | Mobile |