ATI Mobility Radeon HD 3870 X2 vs NVIDIA GeForce 820M
Graphics Processor
| GPU model | M88 | GF117 |
|---|---|---|
| Architecture | TeraScale | Fermi 2.0 |
| Foundry | TSMC | TSMC |
| Manufacturing process | 55 nm | 28 nm |
| Number of transistors | 666 million | 585 million |
| Die size | 192 mm² | 116 mm² |
| GPU variant | — | N15V-GM-B-A2 |
Mobile graphics
| Release date | Sep 1st, 2008 | Nov 27th, 2013 |
|---|---|---|
| Generation | M8x (Mobility HD 3800) | GeForce 800M |
| Production | End-of-life | End-of-life |
| Interface | PCIe 2.0 x16 | PCIe 2.0 x16 |
| Reviews | 2 in our database | — |
| Predecessor | M7x | GeForce 700M |
| Successor | M9x | GeForce 900M |
Clocks
| GPU clock | 660 MHz | 625 MHz |
|---|---|---|
| Memory clock | 850 MHz 1700 Mbps effective | 900 MHz 1800 Mbps effective |
| Shader clock | — | 1250 MHz |
Memory Configuration
| Memory size | 512 MB | 1024 MB |
|---|---|---|
| Memory type | GDDR3 | DDR3 |
| Memory bus width | 256 bit | 64 bit |
| Bandwidth | 54.40 GB/s | 14.40 GB/s |
Render Configuration
| Shading units | 320 | 96 |
|---|---|---|
| TMUs | 16 | 16 |
| ROPs | 16 | 8 |
| Compute units | 4 | — |
| Cache L2 | 256 KB | 128 KB |
| SM count | — | 2 |
| Cache L1 | — | 64 KB (per SM) |
Performance
| Pixel rate | 10.56 GPixel/s | 2.500 GPixel/s |
|---|---|---|
| Texture rate | 10.56 GTexel/s | 10.00 GTexel/s |
| FP32 (float) performance | 422.4 GFLOPS | 240.0 GFLOPS |
| FP64 (double) performance | 84.48 GFLOPS (1:5) | 20.00 GFLOPS (1:12) |
Dimensions & Outputs
| TDP | 110 W | 15 W |
|---|---|---|
| Outputs | No outputs | No outputs |
API Support & Features
| DirectX | 10.1 (10_1) | 12 (11_0) |
|---|---|---|
| OpenGL | 3.3 | 4.6 |
| OpenCL | — | 1.1 |
| Vulkan | — | — |
| Shader model | 4.1 | 5.1 |
| CUDA | — | 2.1 |
