and to put the graphics card on the right side, I recommend the ASUS ROG Strix PCI-E x 16 riser ribbon cable. but you have to be careful when mounting the graphics card. the front screw can be used to fix the graphics card and the rear hole is where the screw fell into the power supply unit, but you can get a good screwdriver that is magnetic and fish the screw out. I only fastened the graphics card with one screw.

I recommend the ASUS ROG RYUJIN 360 water cooling system.

Hoi
I also have ROG Maximus XII Extreme and it fits perfectly in the ROG Strix Helios GX601.
You can also install the graphics card sekrecht, which results in a depth. The negative thing about the case is that I would have imagined it to be a bit smaller. And the lighting is not so bright... the case is rather dark. But you can help yourself out with LED strips. But not the one from Crosair Lighting Node Pro, because it is not compatible with the Aura sing. The case has very cool removable windows and the case has an extra window for the power supply, where the Asus ROG Thor 850P fits perfectly with a watt display. I am thrilled and the assembly is actually very easy and you have space for the cable routing. I had to buy the CableMod PRO extension kit because the CPU connection is, as always, the cable too short.

Thank you for the question. As I have a Corsair Big Tower, I unfortunately cannot comment.

Yes, it fits. The ROG Maximus XII Extreme is based on the E-ATX standard. You just have to check whether the case comes with enough spacers for an E-ATX.