AMD Radeon HD 7870 GHz Edition vs AMD Radeon Sky 900
Graphics Processor
| GPU model | Pitcairn | Tahiti |
|---|---|---|
| GPU variant | Pitcairn XT (215-0828047) | Orthrus |
| Architecture | GCN 1.0 | GCN 1.0 |
| Foundry | TSMC | TSMC |
| Manufacturing process | 28 nm | 28 nm |
| Number of transistors | 2,800 million | 4,313 million |
| Die size | 212 mm² | 352 mm² |
Graphics Card
| Release date | Mar 5th, 2012 | Mar 27th, 2013 |
|---|---|---|
| Generation | Southern Islands | Radeon Sky |
| Production | End-of-life | End-of-life |
| Launch price | 349 USD | — |
| Interface | PCIe 3.0 x16 | PCIe 3.0 x16 |
| Reviews | 95 in our database | — |
| Predecessor | Northern Islands | — |
| Successor | Sea Islands | — |
Clocks
| GPU clock | 1000 MHz | — |
|---|---|---|
| Memory clock | 1200 MHz 4.8 Gbps effective | 1250 MHz 5 Gbps effective |
| Base clock | — | 825 MHz |
| Boost clock | — | 950 MHz |
Memory Configuration
| Memory size | 2 GB | 3 GB |
|---|---|---|
| Memory type | GDDR5 | GDDR5 |
| Memory bus width | 256 bit | 384 bit |
| Bandwidth | 153.6 GB/s | 240.0 GB/s |
Render Configuration
| Shading units | 1280 | 1792 |
|---|---|---|
| TMUs | 80 | 112 |
| ROPs | 32 | 32 |
| Compute units | 20 | 28 |
| Cache L1 | 16 KB (per CU) | 16 KB (per CU) |
| Cache L2 | 512 KB | 768 KB |
Performance
| Pixel rate | 32.00 GPixel/s | 30.40 GPixel/s |
|---|---|---|
| Texture rate | 80.00 GTexel/s | 106.4 GTexel/s |
| FP32 (float) performance | 2.560 TFLOPS | 3.405 TFLOPS |
| FP64 (double) performance | 160.0 GFLOPS (1:16) | 851.2 GFLOPS (1:4) |
Dimensions & Outputs
| Slot width | Dual-slot | Dual-slot |
|---|---|---|
| Length | 241 mm 9.5 inches | 305 mm 12 inches |
| TDP | 175 W | 300 W |
| Suggested PSU | 450 W | 700 W |
| Outputs | 1x DVI1x HDMI2x mini-DisplayPort | 1x DVI1x mini-DisplayPort |
| Power connectors | 2x 6-pin | 2x 8-pin |
| Board number | C401-47 | C476 |
| Width | — | 111 mm 4.4 inches |
API Support & Features
| DirectX | 12 (11_1) | 12 (11_1) |
|---|---|---|
| OpenGL | 4.6 | 4.6 |
| OpenCL | 1.2 | 1.2 |
| Vulkan | 1.2 | 1.2 |
| Shader model | 5.1 | 5.1 |
