There isn't a simple answer to this. The maximum height changes at different lengths due to the chassis, and for the bottom slot, the clips:
But these don't tell the whole story, since you still need some room to be able to maneuver the card in. Plus you're going to have some cards with irregular shrouds that will be taller at the midpoint, but shorter towards the ends. 111mm was a safe recommendation I went with for triple slot cards and/or long cards, since that was all I could really guarantee would fit.
Having said that, for V6 in addition to removing the two clips, I've reduced the flange at the back as well as enlarged the opening at the front. This should at least help with installation of larger cards.
That's perfect. Thanks a bunch.
If I read it correctly and check the drawing, with the latest changes and with out the io: so long as the tallest/thickest portion of a 3 slot GPU less than ~128mm-130mm and less than 299mm in length it would fit. This is pretty great since there are a lot of higher end GPU with slightly taller measurements between 114mm-120mm while still coming in under 300mm. For the extra compatibility I'll take the Ncase without the io any day. Thanks again.