The kernel update "4.9.0-6-amd64 #1 SMP Debian 4.9.82-1+deb9u3 (2018-03-02) x86_64 GNU/Linux" didn't fix the problem for my Dell U2415 (connected to AMD Radeon R9 270X).
- Bug#878221: linux-image-4.9.0-4-amd64: Screen flickers r... Paul Boekholt
- Bug#878221: linux-image-4.9.0-4-amd64: Screen flickers r... Paul Boekholt
- Bug#878221: linux-image-4.9.0-4-amd64: Screen flickers r... Guilherme Ritter
- Bug#878221: linux-image-4.9.0-4-amd64: Screen flickers r... Marco
- Bug#878221: linux-image-4.9.0-4-amd64: Screen flickers r... besy
- Bug#878221: linux-image-4.9.0-4-amd64: Screen flickers r... Yves-Alexis Perez
- Bug#878221: linux-image-4.9.0-4-amd64: Screen flickers r... besy
- Bug#878221: Info received (Bug#878221: linux-image-4.9.0... Vitus Jensen
- Bug#878221: linux-image-4.9.0-4-amd64: Screen flickers r... besy
