ASUS EAH3870 TOP and EAH3850 TOP: Noise, Temperature, Overclockability
Although the reviewed graphics cards come with reference coolers, we measured the level of noise produced by them to see if the fan management settings differ from those of the reference cards. We measured the noise with a digital sound-level meter Velleman DVM1326 using A-curve weighing. The level of ambient noise in our lab was 36dBA and the level of noise at a distance of 1 meter from the working testbed with a passively cooled graphics card inside was 43dBA.
There is no difference: the ASUS EAH3870 TOP is noiseless in every operation mode while the ASUS EAG3850 TOP was only audible under 3D load. The comfortable level of noise was achieved at a price, though: the temperature of the senior model’s GPU was as high as 84°C in idle mode and 92°C in 3D mode. The junior model had a GPU temperature of 64°C when idle and 76-77°C under load. These results shouldn’t worry you at all but they indicate that you’ll need a more effective cooler, like Zalman VF1000 LED, if you want to overclock these graphics cards further.
Our attempt at overclocking proved our apprehensions. The ASUS EAH3870 TOP refused to be overclocked at all hanging up every time we tried to increase its GPU frequency above the default. The ASUS EAH3850 TOP allowed to increase the GPU frequency from 730MHz to 780MHz and remained stable. 50MHz is quite an achievement considering the modest cooler. Perhaps the card could overclock even more if it had a better cooler. Against our expectations, the memory chips could be overclocked from 950 (1900) MHz to 1120 (2240) MHz. This should help achieve the performance of a Radeon HD 3870 in those applications where the amount of graphics memory is not a bottleneck.
Like the reference cards, the ASUS EAH3870 TOP and EAH3850 TOP are perfectly compatible with mainboards supporting PCI Express 1.0a.