AMD Radeon HD 8870 OEM vs NVIDIA GeForce GT 645M
Graphics Processor
| GPU model | Pitcairn | GK107 |
|---|---|---|
| GPU variant | Pitcairn XT (215-0828047) | N13P-GS |
| Architecture | GCN 1.0 | Kepler |
| Foundry | TSMC | TSMC |
| Manufacturing process | 28 nm | 28 nm |
| Number of transistors | 2,800 million | 1,270 million |
| Die size | 212 mm² | 118 mm² |
Graphics Card
| Release date | Jan 8th, 2013 | — |
|---|---|---|
| Generation | Sea Islands | — |
| Production | End-of-life | — |
| Interface | PCIe 3.0 x16 | — |
| Predecessor | Southern Islands | — |
| Successor | Volcanic Islands | — |
Clocks
| GPU clock | 1000 MHz | 709 MHz |
|---|---|---|
| Memory clock | 1200 MHz 4.8 Gbps effective | 900 MHz 1800 Mbps effective |
Memory Configuration
| Memory size | 2 GB | 2 GB |
|---|---|---|
| Memory type | GDDR5 | DDR3 |
| Memory bus width | 256 bit | 128 bit |
| Bandwidth | 153.6 GB/s | 28.80 GB/s |
Render Configuration
| Shading units | 1280 | 384 |
|---|---|---|
| TMUs | 80 | 32 |
| ROPs | 32 | 16 |
| Compute units | 20 | — |
| Cache L1 | 16 KB (per CU) | 16 KB (per SMX) |
| Cache L2 | 512 KB | 256 KB |
| SMX count | — | 2 |
Performance
| Pixel rate | 32.00 GPixel/s | 5.672 GPixel/s |
|---|---|---|
| Texture rate | 80.00 GTexel/s | 22.69 GTexel/s |
| FP32 (float) performance | 2.560 TFLOPS | 544.5 GFLOPS |
| FP64 (double) performance | 160.0 GFLOPS (1:16) | 22.69 GFLOPS (1:24) |
Dimensions & Outputs
| Slot width | Dual-slot | — |
|---|---|---|
| Length | 241 mm 9.5 inches | — |
| TDP | 175 W | 32 W |
| Suggested PSU | 450 W | — |
| Outputs | 1x DVI1x HDMI2x mini-DisplayPort | No outputs |
| Power connectors | 2x 6-pin | — |
| Board number | C401 | — |
API Support & Features
| DirectX | 12 (11_1) | 12 (11_0) |
|---|---|---|
| OpenGL | 4.6 | 4.6 |
| OpenCL | 1.2 | 3.0 |
| Vulkan | 1.2 | 1.1 |
| Shader model | 5.1 | 5.1 |
| CUDA | — | 3.0 |
Other Features
Mobile graphics
| Release date | — | Oct 1st, 2012 |
|---|---|---|
| Generation | — | GeForce 600M |
| Production | — | End-of-life |
| Interface | — | PCIe 3.0 x16 |
| Predecessor | — | GeForce 500M |
| Successor | — | GeForce 700M |
