VR Features

Behind every successful overclocker is a well managed thermal solution. The original HD3870 X2 would be a tough nut to crack on cooling at the moment, so ATi had better done some good work on it.

Mounting holes are 59mm apart diagonally. Thermal pads form the interface for larger semiconductors, and a 12W blower draws air through the skived heatsinks. The module nearer to the fan (presumably the cooler one) is an aluminium unit by default, while the module nearer the exhaust is copper. Conduction does not involve heatpipes.

For an axial blower, the default thermals ran surprisingly silent with fan control at hand. However, load temperatures ran into the eighties. To improve things, we need fan control. RivaTuner works well for that purpose.

Or so we thought. The existing installation of RivaTuner (2.06) has yet to support RV680, so we did a little trick to enable fan control in the nifty program. First you have to download this file and head over here to the RivaTuner installation folder.

Drop the file in and replace the original configuration file. Now when you launch RivaTuner, it should be able to recognise the HD3870 X2.

Tab over to "Fan" and set the fanspeed to your liking. We blasted it up to 100% because we wanted maximum cooling. That alone isn't quite enough.

We cut apart some zip ties and slot them under the original "X" bracket for holding the heatsink modules.

Temperatures shown are those before and after the mounting pressure modification. Load temperatures fell with both the additional fan speed, and mounting pressure.