Temps, power-draw, overclocking
Temperature musings
We perform our testing in an open test bed, with a 120mm fan simulating case airflow.
| Graphics cards | AMD Radeon HD 4870 X2 1,024MiB | Sapphire Radeon HD 4870 512MiB | Sapphire Radeon HD 4850 512MiB | Sapphire Radeon HD 3870 X2 1,024MiB | BFG GeForce GTX 280 1,024MiB | ZOTAC GeForce 9800 GX2 1,024MiB | XFX GeForce GTX 260 896MiB | BFG GeForce 9800 GTX 512MiB |
|---|---|---|---|---|---|---|---|---|
| Ambient temperature | 24°C | 25°C | 21°C | 19°C | 21.5°C | 22°C | 24°C | 21.5°C |
| Idle temperature | 86°C | 71°C | 71°C | 56°C | 47°C | 60°C | 48°C | 52.5°C |
| Load temperature | 87°C | 83°C | 81°C | 80°C | 74°C | 80°C | 72°C | 67°C |
| Ambient-to-load delta | 63°C | 58°C | 60°C | 61°C | 52.5°C | 58°C | 48°C | 45.5°C |
The ambient-to-load delta isn't too much of a concern, but the fact that the idle temperature is, for all intents and purposes, identical to the load's is troubling. ATI really needs to fix the card's BIOS before partners ship them out.
Power-draw
Minimising the skew from different platforms, all cards were run on the ATI platform detailed earlier, other than having a different CPU, QX9650, and differing memory, 4GiB DDR3-1,333.The Canyon test from 3DMark06 was run at 1,920x1,200 with 4xAA and 16xAF.
| Graphics cards | AMD Radeon HD 4870 X1 1,024MiB | Sapphire Radeon HD 4870 512MiB | Sapphire Radeon HD 4850 512MiB | Sapphire Radeon HD 3870 X2 1,024MiB | BFG GeForce GTX 280 1,024MiB | ZOTAC GeForce 9800 GX2 1,024MiB | XFX GeForce GTX 260 896MiB | BFG GeForce 9800 GTX 512MiB |
|---|---|---|---|---|---|---|---|---|
| Idle load | 242 | 149 | 123 | 119 | 127 | 174 | N/A | 141 |
| Full load | 395 | 229 | 203 | 289 | 279 | 313 | N/A | 223 |
Dear Lord! The idle load of the AMD R700 engineering sample is higher than a Radeon HD 4870 running at full chat, and that's because no PowerPlay management was active on the card. The under-load figure is 120W higher than a GeForce GTX 280's - the draw is the highest we've seen. Confirmation, if it was needed, that the engineering sample we've tested is a real power-hungry mutha!
Indications are that things could change in this area, but if not, then we'll not be impressed on this front. We still believe it likely that you'll need a high-quality, high-wattage PSU to power Radeon HD 4870 X2 when it launches but presently the same is true for all extreme multi-GPU set ups.
Overclocking
No overclocking numbers are provided because, at the time of writing,
it wasn't possible to raise the speeds of both cores in a concurrent
fashion. We'll look into this as on-going testing.Wrapping it all up now.
