There will be many different models of the RTX 4090 released (over time). If you find a model the will physically fit in your Aurora R12, you can swap. Hopefully you have a 1000 watt PSU and some added case fans for cooling.

Way to many unknowns at this point.

* Will our SBIOS have an issue with it?
* Will Nvidia write the VBIOS and/or driver to only work with certain chipsets?

RTX 3090 tdp is 350w.  RTX 4090 tdp is 450w.  not good to put it in R12 which has a cramped space.  adding fan would not fundamentally alter this.  it will just circulate hot air inside.  You need a case that has high air flow front to back plus a side panel fan that directly blows cold air on that super high power gpu, or expect it to be roasted.

You have to wait to see what the card from DELL will look like. Aurora R15 will be released soon, and there we will have the opportunity to see the new Rtx 4090 from DELL. It will definitely be a dual fan version as usual.

This one looks like it might fit maybe and it’s liquid cooled. Might have to remove the side panel and rig it up somehow. But like Chris was saying it needs support in other areas. https://youtu.be/TmbOew3HIZk

Does it come with its own nuclear reactor to power it?

I have the oem dual fan rtx 3080 in my r-12 and cooling not an issue due to the proprietary cooling pipes built into this card for this unit. I hope the alienware version of a rtx 4080 card will have a similar build quality and will be ok to upgrade. Although the r15 does look quite a bit wider case wise, we will see.

Would have to wait and see, but the power connector is likely going to be an issue as it uses the new type of connector, and size might also be an issue: "we repositioned the graphics slot to enable larger card designs (up to triple wide cards)."

I am not sure if it will physically fit inside the R12 case, or be compatible with the motherboard.

Bought a new RTX4080 in hopes that it would fit my Alienware Aurora R12 Desktop. As you can see I wasn't disappointed in proving my intuition wrong. Even after I manually created space, 1) my system having trouble updating BIOS, 2) the Nvidia control panel won't open and 3) RTX isn't being detected.