Really tight fit in a Torrent Nano - 7900X3D, RTX 4080, and a lot of drives
Did this build for my adult son. He wanted to max out cooling for really high-end hardware, in a small case, and have room for more drives than PCMR god intended to fit into an ITX build. It took some modding, and use of custom cables helped make it all fit.
The D15S was technically too big. Its heat fins extended too far down for the GPU to fit into the PCI slot. Flipping it upside down almost fixed it, but I still had to shave a few mm off the fins on the bottom. The GPU was still difficult to get into position, but in the end everything was a perfect fit.
I added some acrylic panels with icons from his favorite FPS games. The panel across the top is RGB backlit, and is set to change colors in response to system temps.
All the PSU cables are handmade, and the SATA power cables are all custom fit to reach the drives but not have any excess wiring. I also used SATA data cables with very specific lengths and connector types to minimize cable clutter.