I had the problem as described on Dell Inspiron 1764/Ubuntu 20.04 with 50% of occurence at boot with the screen flickering indefinitely, Linux version 5.15.0-60-generic (buildd@lcy02-amd64-017). I suspected HW but nevertheless tried GRUB configuration modification with no success.
I installed Ubuntu 22.04 and now I have the flicker just during 30seconds of boot. The kernel is the same only the build is different, Linux version 5.15.0-60-generic (buildd@lcy02-amd64-054). Perhaps the build may modify some timings during the boot.
I report my strange experience with flickering.
I had the problem as described on Dell Inspiron 1764/Ubuntu 20.04 with 50% of occurence at boot with the screen flickering indefinitely, Linux version 5.15.0-60-generic (buildd@ lcy02-amd64- 017). I suspected HW but nevertheless tried GRUB configuration modification with no success.
I installed Ubuntu 22.04 and now I have the flicker just during 30seconds of boot. The kernel is the same only the build is different, Linux version 5.15.0-60-generic (buildd@ lcy02-amd64- 054). Perhaps the build may modify some timings during the boot.