A:AnswerI fit an XFX MERC310 7900 XT without issue, including the Z Bar support. Their website lists maximum GPU clearance of 400mm, and your GPU is probably somewhere in the ~320mm range.
A:AnswerTwo SSD spots on the back by cable management and two 3.5" spots on the 3.5 tray near the power supply. Or you can have four 2.5" SSD slots if you use 3.5" to 2.5" adapters on the 3.5 tray.