Long time reader, first time poster. I've been building PCs since pre 286 days.
I bought a 4090 and to accommodate it, I bought a PCIe 5.0 power supply (Thermaltake Toughpower GF3 Gold 1350W) so I didn't have to use the 16-4X8 pin adapter.
I have the Thermaltake L20 GT case which has a fan...