FWIW I have been suffering screenn flickering in Debian 9 since 1 or 2 weeks ago. The flickering is _very_ serious: it makes my box almost unusable.
Booting with kernel option: i915.enable_rc6=0 significantly reduces the problem but it doesn't completely fix it. Instead the following fix works: Create a file: /usr/share/X11/xorg.conf.d/10-fix-screen-flickering.conf with content: --8<-----------------------------cut here---------------start------------->8--- Section "Device" Identifier "Intel Graphics" Driver "intel" Option "AccelMethod" "uxa" EndSection --8<-----------------------------cut here---------------end--------------->8--- Best regards, Tino
