That space doesn't have to be wasted though, which is the idea I've incorporated into the M5 design (see the pics in these posts). Most people aren't going to use those last few slots of an ATX motherboard, so why not design it to support a radiator (or other things) in that space instead?Regarding 'waste of space' & ATX, I am referring to the extra slots (that I personally would not have a need for, which is why I gravitate towards ITX systems) & the empty space above those unused slots...