What's better for a CAD build, 1x Quadro P400 or 2x 1080s in Sli?

[rapiergv]

Hey guys!
Basically the title. Considering the build is meant for heavy CAD work (ArchiCAD and AutoCAD) and disregarding CPU/RAM/Mobo/SSD, can you guys help me out in this dilemma? Is the Quadro definitely better?
It would be awesome if you could provide some reasons/explanations as well.
Thank you very much in advance!

 

[okcnaline]

Quadro and a whole crapton of cores and RAM. Nothing is rendered for a 2D AutoCAD drawing anyways.