AMD Radeon 550X 640SP vs ATI Radeon HD 4870 Mac Edition
Graphics Processor
| GPU model | Lexa | RV770 |
|---|---|---|
| GPU variant | Lexa PRO (215-0904018) | RV770 XT Mac (215-0669080) |
| Architecture | GCN 4.0 | TeraScale |
| Foundry | GlobalFoundries | TSMC |
| Manufacturing process | 14 nm | 55 nm |
| Number of transistors | 2,200 million | 956 million |
| Die size | 103 mm² | 256 mm² |
Graphics Card
| Release date | Apr 11th, 2018 | Jan 6th, 2009 |
|---|---|---|
| Generation | Polaris | Radeon R700 |
| Production | End-of-life | End-of-life |
| Interface | PCIe 3.0 x8 | PCIe 2.0 x16 |
| Predecessor | Polaris | Radeon R600 |
| Successor | Vega | Evergreen |
| Reviews | — | 135 in our database |
Clocks
| Base clock | 1019 MHz | — |
|---|---|---|
| Boost clock | 1071 MHz | — |
| Memory clock | 1500 MHz 6 Gbps effective | 850 MHz 3.4 Gbps effective |
| GPU clock | — | 750 MHz |
Memory Configuration
| Memory size | 4 GB | 512 MB |
|---|---|---|
| Memory type | GDDR5 | GDDR5 |
| Memory bus width | 64 bit | 256 bit |
| Bandwidth | 48.00 GB/s | 108.8 GB/s |
Render Configuration
| Shading units | 640 | 800 |
|---|---|---|
| TMUs | 40 | 40 |
| ROPs | 16 | 16 |
| Compute units | 10 | 10 |
| Cache L1 | 16 KB (per CU) | 16 KB (per CU) |
| Cache L2 | 256 KB | 256 KB |
Performance
| Pixel rate | 17.14 GPixel/s | 12.00 GPixel/s |
|---|---|---|
| Texture rate | 42.84 GTexel/s | 30.00 GTexel/s |
| FP16 (half) performance | 1,371 GFLOPS (1:1) | — |
| FP32 (float) performance | 1,371 GFLOPS | 1,200 GFLOPS |
| FP64 (double) performance | 85.68 GFLOPS (1:16) | 240.0 GFLOPS (1:5) |
Dimensions & Outputs
| Slot width | IGP | Dual-slot |
|---|---|---|
| TDP | 50 W | 150 W |
| Suggested PSU | 250 W | 450 W |
| Outputs | 1x DVI1x HDMI1x DisplayPort | 1x DVI1x mini-DisplayPort |
| Power connectors | None | 2x 6-pin |
| Length | — | 250 mm 9.8 inches |
| Board number | — | B771 |
API Support & Features
| DirectX | 12 (12_0) | 10.1 (10_1) |
|---|---|---|
| OpenGL | 4.6 | 3.3 |
| OpenCL | 2.1 | 1.1 |
| Vulkan | 1.2 | — |
| Shader model | 6.4 | 4.1 |
