Comment # 25 on bug 78439 from Andrius Štikonas

Created attachment 115644 [details]
dmesg.txt.xz (lower modes, reattaching)

only the lower modes are enabled:

{  324000, 0x06, 2 },
{  162000, 0x06, 1 }

When booting, everything starts fine. After reattaching DP connector, the right
side of the screen flickers. (Note that flickering in 648 mode is more severe,
affects the whole screen and even causes blinking of the screen)