I wanted to change my old case with the 400R H50 and H100 and keep my ASUS P5Q-E Q9650 processor. First, get the tapes from the back plate of H50 was a challenge and there is still a residue. Then I moved to the MB to the 400R, installed the H100 and found there was not enough room for the rear of the two fans on the rad for the reason that the heat sink fins on the top was too P5Q-E high.
I will try to loosen the screws to replace MB in the pump and then tighten back up in case the MB. Do not know if I'm imagining the problem of deformation MB.I think my main complaint with Corsair is surprise MB heat sink interference.