yeah i used to have the same prob with other cases not being able to fit in 3 double slot cards thats how i went with a 700D everything fits in here with a ton of extra space to boot! (oops just noticed its your mobo layout)
yeah man they can really take the heat like the 8, 9 2xx series all which are rated to take up to 104 aswell but like i said up there no way u want them running over 80 for long term life wise i would think and leave u with a pain in the but of RMA's 2 of my cards were from OCUK and ive heard a lot of horror stories from there rma's over the years