AMD Radeon HD 7870M vs AMD Radeon R9 255 OEM
Graphics Processor
| GPU model | Heathrow | Cape Verde |
|---|---|---|
| GPU variant | Heathrow XT (216-0835033) | Cape Verde PRX |
| Architecture | GCN 1.0 | GCN 1.0 |
| Foundry | TSMC | TSMC |
| Manufacturing process | 28 nm | 28 nm |
| Number of transistors | 1,500 million | 1,500 million |
| Die size | 123 mm² | 123 mm² |
Mobile graphics
| Release date | Apr 24th, 2012 | — |
|---|---|---|
| Generation | London (HD 7800M) | — |
| Production | End-of-life | — |
| Interface | PCIe 3.0 x16 | — |
| Predecessor | Vancouver | — |
| Successor | Solar System | — |
Clocks
| GPU clock | 800 MHz | — |
|---|---|---|
| Memory clock | 1000 MHz 4 Gbps effective | 1150 MHz 4.6 Gbps effective |
| Base clock | — | 900 MHz |
| Boost clock | — | 930 MHz |
Memory Configuration
| Memory size | 2 GB | 2 GB |
|---|---|---|
| Memory type | GDDR5 | GDDR5 |
| Memory bus width | 128 bit | 128 bit |
| Bandwidth | 64.00 GB/s | 73.60 GB/s |
Render Configuration
| Shading units | 640 | 512 |
|---|---|---|
| TMUs | 40 | 32 |
| ROPs | 16 | 16 |
| Compute units | 10 | 8 |
| Cache L1 | 16 KB (per CU) | 16 KB (per CU) |
| Cache L2 | 256 KB | 256 KB |
Performance
| Pixel rate | 12.80 GPixel/s | 14.88 GPixel/s |
|---|---|---|
| Texture rate | 32.00 GTexel/s | 29.76 GTexel/s |
| FP32 (float) performance | 1,024 GFLOPS | 952.3 GFLOPS |
| FP64 (double) performance | 64.00 GFLOPS (1:16) | 59.52 GFLOPS (1:16) |
Dimensions & Outputs
| TDP | 45 W | 65 W |
|---|---|---|
| Outputs | No outputs | No outputs |
| Slot width | — | Dual-slot |
| Suggested PSU | — | 250 W |
| Power connectors | — | 1x 6-pin |
| Board number | — | C750 |
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 |
Other Features
Graphics Card
| Release date | — | Dec 21st, 2013 |
|---|---|---|
| Generation | — | Volcanic Islands |
| Production | — | End-of-life |
| Interface | — | PCIe 3.0 x16 |
| Predecessor | — | Sea Islands |
| Successor | — | Pirate Islands |
