Hey Everyone,
I know this belated. It's because I've been working with a couple different factories with this new design. There are a few hurdles to overcome as this project moves forward. Specifically it's a process of simplifying and refining the design.
I left you guys off at what application I'll be using for accommodating various thickness of gpus. The solution I've decided to go with is to incorporate a slot that can allow the user to move the motherboard bracket side to side by about 10-12mm. This would allow gpu thickness up to 3 slot at the cost of cpu clearance. Especially with the new nvidia gpus this will be very nice.
Also, there will be an optional lower plate swap one can purchase to change the default dual chamber layout to a traditional layout with the gpu connected directly to the motherboard. This will give a lot more options for customization and cooling. After looking at the spacing for this trad layout for the 15.4 L version, it would be possible to use a 280mm rad in the trad layout if you use a pump/block combo. (This is still up for testing and hopefully I can get these benchmarks to all of you soon).
@CarbonPark , as for the rear IO, a lot of people have been asking about this. The end intent is to provide different IO plate options, however the default IO plate will likely have additional through holes for users that need more usb slots and audio etc.