so you are “watercooling” your cpu, but not your gpu.
I would suggest putting the AIO cpu cooler radiator in front, and exhaust in top. (cold air, instead of hot air from GPU)
…or reverse the fans so you are pushing air out of the case in front, and pulling air from the top the case.
GPU ASUS ROG Strix RTX 4090 NonOC/OC have very good default cooler, temperature are ok.
But CPU Sapphire Rapids with 56 P-Cores (112Threads) really need water. Without water is it not good. Looks on 13900/14900/K/KS
Ane here are only P-Cores and it is so many more cores.
Cold air goes from the front through the gpu to the back. Very warm air from the CPU goes straight up of the case out.
I tried many variations and this one turned out to be the most optimal. My case Fractal Define 7 XL has a special made front part that has ventilation holes from Coldzero.
The temperature approximate:
Idle GPU +-37 (hot spot +-46) GPU memory +-40, CPU +-35
Under load GPU +-60/65, CPU +-50/55 (tjmax +-67)