I have a Laptop with an AMD Graphics Card (Radeon HD 6770M) and an Intel card. My OS is Debian 8 (64-bit).
I installed the AMD drivers for the video-card (fglrx) as described here. Running glxinfo I can clearly see that direct rendering is being used, and that the AMD card is enable. However, if I run a 3D application like glxgears, I can hear some high-pitch noises coming from the laptop, which stop a soon as glxgears is stopped. These noises sound like electrical noises and are not from the fan, and I'm afraid that I may damage the card if I keep using it.
I also have Windows 7 installed on the same machine, and with it I do not hear any weird noise (only the fan, obviously), so I believe it is not a hardware failure, but something related to the drivers. Using the Intel card on Linux there are also no noises.
Checking with aticonfig, I verified that the clocks are normal (Core: 750MHz, Memory:800MHz).
Is there anything I can do to stop these noises? Or is this card not compatible with Linux?