With last upgrade to Ubuntu 14.10, (kernel 3.16.0-23-generic + fglrx 14.2), this bug is now solved with acpi_osi=Linux on linux boot command line.
So, I would propose to close the bug.
With last upgrade to Ubuntu 14.10, (kernel 3.16.0-23-generic + fglrx 14.2),
this bug is now solved with acpi_osi=Linux on linux boot command line.
So, I would propose to close the bug.