Bug#878221: linux-image-4.9.0-4-amd64: Screen flickers randomly with Radeon R9 270X since upgrade from 4.9.0-3 to 4.9.0-4

[Paul Boekholt]

I've switched to linux-image-4.13.0-0.bpo.1-amd64 from the backports repository.
It does not seem to flicker, though now my computer won't wake up from sleep.