airtight seal around ZIF socket w/ very little room for air when mounted, or use dielectric cgreese anywhere where air may end up. My unit runs 24/7 and I have alot less insulation than you do, I used a 1/2" thick peice of closed cell foam on the bakc plate held down by a 1/4" peice of lucite, and used a bit of dielectric greese on the outer perimeter to make sure air didn't get in, and about the same on the fron,t, an armaflex "donut" with a bit of dielectric greese on the bottom to ensure an airtight seal on the mobo. I've found that insulating the motherboard ot that degree really doesn't help much, but it doesn't hurt either.
