U can check subthreads to the GPU and motherboards. They are separated by vendor and chipset.
Also many good things for OC you can find on Massman Youtube channel (most of them since LGA1151 and AM4 to latest):
https://www.youtube.com/c/SkatterBencher/playlists
Or for modern or also older setups like LGA775 here:
https://www.youtube.com/c/LuumiJuhani/featured
https://www.youtube.com/c/TechTested/videos
And for oldbench system:
https://www.youtube.com/c/philscomputerlab/videos
https://www.youtube.com/channel/UC306-gSG9W9_9ZAfqwubEhQ
https://www.youtube.com/c/RETROHardware/videos
GPU overlcocking, modding
https://www.youtube.com/c/TecLabbyRbuass
https://www.youtube.com/c/MCMXtreme/videos
https://www.youtube.com/c/UnleashedOverclocking/videos
There are more channels, but I think, for the start is it enough