AMD Radeon HD 7870 GHz Edition & HD 7850 Review
Earlier this week AMD took the wraps off the latest entries into its Radeon HD 7000 series, the Radeon HD 7870 GHz Edition (GE) and the Radeon HD 7850. The HD 7800 family is billed as a replacement to the HD 6900 series. From a price and specifications standpoint, that looks to be the case. The "flagship" models in the HD 6000-series (the 6970 and 6950) each had 2GB of VRAM and carried price tags of $349 and $279. The 7800 family has the same 2GB of VRAM (as expected, considering that the 7900 family came with 3GB), and price points of $349 and $249.
In their press materials, AMD bills the Radeon HD 7800 "Pitcairn" platform with the tagline "Serious gaming starts here". Two generations ago, with the launch of the Radeon HD 5870 and Eyefinity, the x800 family was seen as the flagship and the x900 moniker was reserved for the dual-GPU card (the Radeon DH 5970). The 6000-series moved the flagship "enthusiast" cards into the x900 family (the HD 6970 and the HD 6950) and edged up the dual-GPU to carry the top end of the naming with the HD 6990 badging.
The 6800 family was great in widescreen, but could be hampered in Eyefinity to the 1GB VRAM limitation. The 6900 was reserved for high-end Eyefinity gaming, due to carrying 2GB of VRAM. The 7800 family now sports the 2GB of VRAM of the enthusiast class cards in the "performance" tier, but it also now sports the $350 - $250 price range of the 6900 series.
Architecture & Specs
Spec-wise, the Radeon HD 7870 and 7850 slot in between the 6800 and 6900 families - though remember it is on the new GCN architecture.
| Card | GPUs | Transistors | Memory | Bus Width | Shaders | Clock (MHz) | TDP (Watts)* | Power | MSRP | ||
| Core | Mem | Idle | Max | ||||||||
| AMD Radeon HD 7970 | 1 | 4.3B on 28nm | 3GB | 384-bit | 2,048 | 925 | 1,375 | <3 | 250* | 8+6-pin | $549 |
| AMD Radeon HD 7950 | 1 | 4.3B on 28nm | 3GB | 384-bit | 1,792 | 800 | 1,250 | <3 | 200* | 6+6-pin | $449 |
| AMD Radeon HD 7870 | 1 | 2.8B on 28nm | 2GB | 256-bit | 1,280 | 1,000 | 1,200 | <3 | 175* | 6+6-pin | $349 |
| AMD Radeon HD 7850 | 1 | 2.8B on 28nm | 2GB | 256-bit | 1,024 | 860 | 1,200 | <3 | 130* | 6-pin | $249 |
| AMD Radeon HD 6970 | 1 | 2.6B on 40nm | 2GB | 256-bit | 1,536 | 880 | 1,375 | 20 | 250* | 8+6-pin | $349 |
| AMD Radeon HD 6950 | 1 | 2.6B on 40nm | 2GB | 256-bit | 1,408 | 800 | 1,250 | 20 | 200* | 6+6-pin | $279 |
| AMD Radeon HD 6870 | 1 | 1.8B on 40nm | 1GB | 256-bit | 1,120 | 900 | 1,050 | 19 | 151 | 6+6-pin | $239 |
| AMD Radeon HD 6850 | 1 | 1.8B on 40nm | 1GB | 256-bit | 960 | 775 | 1,000 | 19 | 127 | 6-pin | $179 |
| *These values represent the maximum wattage allowed through the AMD PowerTune. Idle for the 7000-series is based on a "long idle" scenario. | |||||||||||