Temps, overclocking, power-draw
We perform our testing on an open test-bed with a 120mm fan simulating case airflow.
| Graphics cards | BFG GeForce GTX 295 1,792MB |
Inno3D GeForce GTX 280 1,024MB |
Inno3D GeForce GTX 260 OC 896MB |
Sapphire Radeon HD 4870 X2 2,048MB |
Sapphire Radeon HD 4850 X2 2,048MB |
|---|---|---|---|---|---|
| Ambient temperature | 20.5°C | 21.5°C | 19.7°C | 24°C |
22°C |
| Idle temperature | 47°C | 47°C | 47°C | 73°C |
42.5°C |
| Load temperature | 72°C | 74°C | 70°C | 95°C | 62.5°C |
| Ambient-to-load delta | 51.5°C | 52.5°C | 50.3°C | 71°C | 41°C |
What a difference a die-shrink can make. The 55nm GeForce GTX 295 is significantly cooler under load than a 2GB Radeon HD 4870 X2. Better still, it's a touch cooler than a single-GPU GeForce GTX 280, that new heatsink-and-fan solution is clearly doing the trick.
Power-draw
| Graphics cards | BFG GeForce GTX 295 1,792MB |
BFG GeForce GTX 280 OC | Sapphire Radeon HD 4870 X2 2,048MB |
Sapphire Radeon HD 4850 X2 2,048MB |
|---|---|---|---|---|
| Idle draw | 133W | 107W | 149W |
138W |
| Load draw | 307W | 260W | 366W | 275W |
Overclocking
As mentioned earlier, NVIDIA chose not to bump up the frequencies of the dual-GPU GeForce GTX 295, opting instead to raise the shader-count to GTX 280 levels. Given the efficiency attained from a 55nm shrink, our temperature readings hint at ample overclocking headroom.
With no additional cooling, we managed to raise the default frequencies of 576MHz, 1,242MHz and 1,998MHz - for core, shader and memory, respectively - to a very decent 684MHz, 1,474MHz and 2,400MHz. By doing so, the average framerate at 1,920x1,200 in Enemy Territory: Quake Wars rose from 127.43fps to 131.30fps.
We're certain to see overclocked parts from NVIDIA's various partners in the near future.
