hi
I think it depends if you have a radiator installed, the strix RX580 at 298mm is an exact fit with zero clearance against the AP183 (32mm) and magicool 2x180 radiator (35mm) with the case original filter brackets removed.
So this gives you 365mm of space for all the cooling stuff and video...
I thought the rad may stay loose if I don't mount it to anything.
However, after doing some measurements it seems my worries are really not that of a problem.
It seems the rad will fit in just well with not much space to giggle around.
So I may just go ahead and get the rad and stuffs soon...