[NAME]    . . . since a Founder's Edition RTX 3090 can fit into an Aurora R11.  This is where you are going wrong.  The RTX 3090 that comes in the Aurora R11 is NOT nVidia Founders Edition . . . but rather a Dell proprietary version sourced from MSI.  Obviously, it is much shorter than the nVidia RTX 3090 FE graphics card.
Today I was doing some calculations before buying this card. So firstly I compared the size of the cases between the Aurora R11 and Aurora R9. In the end, I found out they were exactly the same. Moving on, secondly, I compared the sizes of the two cards length wise, the Founder's Edition of the RTX 3090 is 314mm or 31.4cm and the Gigabyte 3090 is 320mm or 32cm. So I assumed that there would be 0.6cm of clearance for the card to fit into my Aurora R9 since a Founder's Edition RTX 3090 can fit into an Aurora R11. After that, I opened up my Aurora R9 to check how much room I have, and I only have about 27cm which is 5cm off; there is a fan blocking the way but if I were to remove that then I would only have 29cm of clearance which still isn't enough. Although I don't understand how you can fit a 31.4cm graphics card into an Aurora R11 which has the exact same dimensions as the Aurora R9 when I have barely any room in mine. Am I measuring something incorrectly, or is it just false statistics?
Aurora R9, Gigabyte GeForce RTX 3090 Gaming OC fit in the case?