The board is an (large) ATX layout from what I can tell. The system uses an IO panel similar to most Dell desktop systems, which has the powerbutton and some USB ports. This uses a single ribbon cable and there doesn't seem to be any documentation with the pin-out. This would mean you'd have to build the IO panel into your chassis of choice, which may take some serious planning.

In other words, I'd suggest sticking with the Dell case or looking for a "retail" motherboard to build your system from.