I'm running a 5850 and a 5870 w/ crossfire. The 5850 is overclocked to the 5870's speed. The 5870 is the top card. But my problem is with the bottom card, the 5850. When I apply a profile w/ automatic fan control, the fan on my first card reacts as programmed in the profile. The fan in the second control generally does not react. It just maintains a steady speed of 20%. Even when I have "Synchronize settings for similar graphics processors" enabled. However, in rare instances, the second card will react and follow the profile as programmed. I don't know what prompts this, but it only happens after I've had the computer on for a good hour or so. It is not prompted by activity. In other words, even when I start a game-up and the 2nd GPU becomes active, this has no effect. I don't know if this is relevant, but when I open CCC (with afterburn closed), the temperature reading on my second card appears as 0 when inactive. Moreover, I am unable to adjust the fan speeds of either card in CCC. I don't know what I'm doing wrong here, but it sucks.
eactly the same problem Running two HD5970 (two duel GPU cards), one made by Asus, the other Sapphire. Running version 2.10 as you can see. Not so much an issue doing Windows tasks, but when I start gaming the temps on GPU1 & 2 get out of control and and cause errors and worst case BSOD. I've been playing around with selecting alternate GPUs in the settings and when GPU2 (master on card in question, but slave in array), Fan Speed (%) is greyed out. Running new Beta Drivers, for details see below. Drivers Temps
