AMD Radeon HD 7870 XT vs NVIDIA GeForce GTX 660 Rev. 2
Graphics Processor
| GPU model | Tahiti | GK104 |
|---|---|---|
| GPU variant | Tahiti LE (215-0821122) | — |
| Architecture | GCN 1.0 | Kepler |
| Foundry | TSMC | TSMC |
| Manufacturing process | 28 nm | 28 nm |
| Number of transistors | 4,313 million | 3,540 million |
| Die size | 352 mm² | 294 mm² |
Graphics Card
| Release date | Nov 19th, 2012 | Sep 13th, 2014 |
|---|---|---|
| Generation | Southern Islands | GeForce 600 |
| Production | End-of-life | End-of-life |
| Launch price | 270 USD | — |
| Interface | PCIe 3.0 x16 | PCIe 3.0 x16 |
| Reviews | 95 in our database | 77 in our database |
| Predecessor | Northern Islands | GeForce 500 |
| Successor | Sea Islands | GeForce 700 |
Clocks
| Base clock | 925 MHz | 980 MHz |
|---|---|---|
| Boost clock | 975 MHz | 1032 MHz |
| Memory clock | 1500 MHz 6 Gbps effective | 1502 MHz 6 Gbps effective |
Memory Configuration
| Memory size | 2 GB | 2 GB |
|---|---|---|
| Memory type | GDDR5 | GDDR5 |
| Memory bus width | 256 bit | 192 bit |
| Bandwidth | 192.0 GB/s | 144.2 GB/s |
Render Configuration
| Shading units | 1536 | 960 |
|---|---|---|
| TMUs | 96 | 80 |
| ROPs | 32 | 24 |
| Compute units | 24 | — |
| Cache L1 | 16 KB (per CU) | 16 KB (per SMX) |
| Cache L2 | 512 KB | 384 KB |
| SMX count | — | 5 |
Performance
| Pixel rate | 31.20 GPixel/s | 20.64 GPixel/s |
|---|---|---|
| Texture rate | 93.60 GTexel/s | 82.56 GTexel/s |
| FP32 (float) performance | 2.995 TFLOPS | 1.981 TFLOPS |
| FP64 (double) performance | 748.8 GFLOPS (1:4) | 82.56 GFLOPS (1:24) |
Dimensions & Outputs
| Slot width | Dual-slot | Dual-slot |
|---|---|---|
| Length | 267 mm 10.5 inches | 241 mm 9.5 inches |
| TDP | 185 W | 140 W |
| Suggested PSU | 450 W | 300 W |
| Outputs | 1x DVI1x HDMI2x mini-DisplayPort | 2x DVI1x HDMI1x DisplayPort |
| Power connectors | 2x 6-pin | 1x 6-pin |
| Board number | C474 | P2004 SKU 11 |
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 |
