It will be very interesting too see how the 3080s and 3090 peform thermally then considering they have a similar TDP, i have a suspicion a slim 240 rad like the alphacool or the EK (i say these ones as their the easiest to fit) may not be able to handle both the cpu and gpu comfortably, may be better air cooling cpu? Cant wait to see how these perform. (im sure @fabio will grab a 3090 and throw it into his rig to see how it performs)That's me actually! And temps are toasty. Side panels in in heaven loop until steady state coolant temp reached 59.7C (but my small office warmed up during this, started at 25C and by the end 29-30C. This is just stressing GPUs, very little load on CPU. What I can tell you is have some good air conditioning while gaming... My cards are undervolted and have a combined draw of 330 watts (don't ask why the 2nd card is only under 60% load, I don't know why).
Thermal data is at the end of the imgur album.