Comment # 10 on bug 91202 from Vedran Miletić

Further information: this bug does not occur on R9 380, tested with

01:00.0 VGA compatible controller [0300]: Advanced Micro Devices, Inc.
[AMD/ATI] Tonga PRO [Radeon R9 285/380] [1002:6939] (rev f1) (prog-if 00 [VGA
controller])

Dual DVI using DVI-I and DVI-D works fine.