So unless you have a GTX Titan Black/Titan Z (or that one MSI version of the R280X with 6GB), Ultra is off-limits - even with a 970/980.
Looks like Nvidia needs to get to work on the 980Ti, stat. For now, I'll be stuck at medium textures with my 2GB 680 (if that - I'm rendering to a 1440p, not 1080p, target).
I'm not complaining, though - we spent long enough with 8800GTs as minimum and a lack of motivation to move to ever faster, more RAM-laden cards. Glad to see the consoles are actually driving PC specs forward this time around...