The tests were performed in a controlled air conditioned room with temperatures maintained at a constant 25c – a comfortable environment for the majority of people reading this.
Idle temperatures were measured after sitting at the desktop for 30 minutes. Load measurements were acquired by playing Crysis Warhead for 30 minutes and measuring the peak temperature. We also have included Furmark results, recording maximum temperatures throughout a 30 minute stress test. All fan settings were left on automatic.
1.12 Voltage setting
Let’s break down the results above. Firstly at 830MHz core, the card voltage is set to 1.12. Under Furmark load, the card never exceeds 50%, maintaining temperatures of 74c when gaming.
This rises to 82c when using the earlier version of Furmark and 88c with the latest V1.9.0 (set to extreme burning mode). These are not realistic ‘real world’ load conditions but are included for interest.
The fan rotates at 28 percent when idle, which translates to a speed around 1,400 rpm. Under load, at 50 percent this rises to around 2,900 rpm. As documented on the previous page, this produces a noise emission around 40 dBA.
1.175 Voltage setting
When the card is set to the performance or ‘OC’ mode, the voltage increases to 1.175. When loaded in Furmark the card fan profile changes, causing a ‘shift’ in fan speed between 50 percent and 65 percent.
Above you can see the temperature graph which is dipping and rising as the fan speed fluctuates between 2,900 rpm and 3,700 rpm. This causes a rather annoying fan whine on a fairly regular basis as the profile is adjusting the fan speed to compensate for rising (and dropping) temperatures. While this can be unpleasant (causing noise emissions to peak over 48 dBA), it isn’t really indicative of a real world gaming scenario.
Below we have included a video showing the effectiveness of the AMD HD6990 cooler after being loaded in Furmark and returning to ‘idle’ temperatures. It takes several minutes for the card to achieve an ambient state.AMD Radeon HD6990 Review,