Right before new year a new piece of hardware candy has found us. The graphics card HD 7770 “Cape Verde” has been detailed and benchmarked. The card will be the first ever to be specified to 1 GHz at stock speed.
Pitcairn that will be used in the HD 7800 series is still missing, but Cape Verde is not shy to show its colors. Besides being benchmarked detailed specifications has surfaced. A picture of the back of the card has four more memory circuits, which means HD 7770 will sport no less than 2 GB GDDR5 memory. One might wonder if such a large buffer is worthwhile on a card like this, but at the same time it should no affect store prices noticeably.
| Model | HD 7770 “Cape Verde XT” | HD 7970 “Tahiti XT” | HD 7950 “Tahiti Pro” |
| Node | 28nm | 28nm | 28nm |
| Die size |
164 mm² | 365mm² | 365mm² |
| Architecture | GCN | GCN | GCN |
| GCN units |
14 | 32 | 28 |
| Radeon cores |
896 | 2048 | 1792 |
| GPU frequency |
1000 MHz | 925 MHz | 900 MHz |
| TFLOPS | 1.792 | 3.789 | 3.226 |
| Memory buffer |
2 GB(?) GDDR5 | 3 GB GDDR5 | 3 GB GDDR5 |
| Memory bus |
128-bit | 384-bit | 384-bit |
| Memory frequency |
1125 MHz (4500 MHz effectively) |
1375 MHz (5500 MHz effectively) |
1250 MHz (5000 MHz effectively) |
| Memory bandwidth |
72 GB/s | 264 GB/s | 240 GB/s |
| ROPs | 16 | 32 | 32 |
| Texture units |
56 | 128 | 112 |
| TDP | ~90-100W(?) | 250W | ? |
The graphics card will be the first to launch at 1000 MHz reference clock, which just keeps confirming to us that this is an architecture that overclocks well and the process from TSMC is healthy. The memory frequency is only at 4500 MHz, connected to a 128-bit memory bus adds up to 72 GB/s – HD 5770/6770 is at 76.8 GB/s. This could be because the specifications of the card is not finalized or that the new architecture simly has better memory handling. But both clock frequencies of the GPU and memory might change before launch, which is slated for March.
 |
 |
HD 7770 with early drivers scores P3421/X1077 in 3DMark 11 which puts its well above GTX 550 Ti and HD 6770. As it stands today the card is about 5 percent slower than. Even if the card may not be the replacement for the HD 6800 series that we hoped for the TDP will land at around 90-100W. The price is expected to be around $149.
Source: Chiphell
