XPS Questions

I am now retired and doing 3D architectural modeling and some astrophysics modeling to try and maintain my sanity.

I read somewhere (fog of age) that the XPS 8900 series does not have room to install the NVIDIA GTX 1070 card.  Is this true?  The same comments were making disparaging remarks about the amount of available cooling but it was pretty obvious the individual had likely not received a pony as a child.

Due to the computational density of the astrophysics model (objects in the Oort cloud if interested), I need some fairly serious CPU and will play games, read emails or watch movies on my Kindle Fire HDX to reduce all unnecessary CPU drains while running my model.

Okay, I confess that I love the XPS line and this would be my 4th purchase.  Sorry, Dell, I do not purchase them directly from you because I have to include in home service as part of the deal.

Is the XPS limited to the NVIDIA 9 series as the top end card (note:  I do understand that I could purchase two but that is a sub optimal solution for a couple of reasons) or by any chance have their competitors come close and have something that would serve my need (not my primary choice).

Out of curiosity, why are there so few XPS desktops with SSD options?  In all honesty, I really miss the old days when you could simply click and build what you wanted but I digress.

Any help is appreciated.

Very old XPS addicted user