Ah, gotcha. 939SLI32 is fairly clear around the NB's immediate vicinity, but not overly so. Thermaltake's Crystal Orb and Vantec's Copper chip cooler won't fit at all due to stuff in the way. Also, the Northpole or XE will not work on the SB as there's some serious crowding there. For that I use Thermalright's HR-05 though it's quite a bit higher than 47mm but does have a very small footprint which just covers the chip.
What don't kill me will eventually.