AMD Radeon HD 8870M vs AMD Radeon RX 640 Mobile
Graphics Processor
| GPU model | Venus | Polaris 23 |
|---|---|---|
| GPU variant | Venus XT | Polaris 23 XT |
| Architecture | GCN 1.0 | GCN 4.0 |
| Foundry | TSMC | GlobalFoundries |
| Manufacturing process | 28 nm | 14 nm |
| Number of transistors | 1,500 million | 2,200 million |
| Die size | 123 mm² | 103 mm² |
Mobile graphics
| Release date | Apr 1st, 2013 | May 13th, 2019 |
|---|---|---|
| Generation | Solar System (HD 8800M) | Mobility Radeon (M600) |
| Production | End-of-life | Active |
| Interface | PCIe 3.0 x16 | PCIe 3.0 x8 |
| Predecessor | London | Crystal System |
| Successor | Crystal System | — |
Clocks
| Base clock | 725 MHz | 1082 MHz |
|---|---|---|
| Boost clock | 775 MHz | 1218 MHz |
| Memory clock | 1125 MHz 4.5 Gbps effective | 1500 MHz 6 Gbps effective |
Memory Configuration
| Memory size | 2 GB | 2 GB |
|---|---|---|
| Memory type | GDDR5 | GDDR5 |
| Memory bus width | 128 bit | 64 bit |
| Bandwidth | 72.00 GB/s | 48.00 GB/s |
Render Configuration
| Shading units | 640 | 640 |
|---|---|---|
| TMUs | 40 | 40 |
| ROPs | 16 | 16 |
| Compute units | 10 | 10 |
| Cache L1 | 16 KB (per CU) | 16 KB (per CU) |
| Cache L2 | 256 KB | 512 KB |
Performance
| Pixel rate | 12.40 GPixel/s | 19.49 GPixel/s |
|---|---|---|
| Texture rate | 31.00 GTexel/s | 48.72 GTexel/s |
| FP32 (float) performance | 992.0 GFLOPS | 1.559 TFLOPS |
| FP64 (double) performance | 62.00 GFLOPS (1:16) | 97.44 GFLOPS (1:16) |
| FP16 (half) performance | — | 1.559 TFLOPS (1:1) |
Dimensions & Outputs
| TDP | unknown | 50 W |
|---|---|---|
| Outputs | No outputs | No outputs |
| Slot width | — | Dual-slot |
| Power connectors | — | None |
API Support & Features
| DirectX | 12 (11_1) | 12 (12_0) |
|---|---|---|
| OpenGL | 4.6 | 4.6 |
| OpenCL | 1.2 | 2.1 |
| Vulkan | 1.2 | 1.2 |
| Shader model | 5.1 | 6.4 |
