its not a Maximus Issue.

its a total Asus Heatsink Issue.
I've had many many 775 boards in the last year or two with these mosfet heatsinks on them.
they never make good contact with all mosfets, especially in actual use of the board, when they start to warp alittle from just about anything. crooked case, torqing the board. heavy watercooling pulling the board. heavy heatsinks warping the board over time.
waterblocks with no backplate, or cheap backplates.
every single time I took my heatpipe/heatsinks off the board, the contact in the thermal pad was near non existant in the middle. or very inconsistent.

what I resorted to, was nuts and bots, and my own back plates I made from strips of metal and a drill.
now, I dont have to worry about bowing making the mosfets lose contact.

in my opinion, these heatsinks should come with back plates by default.