With your 7700 you probably will see an increase in ambient temp if you run the intake tube type deal.
The only trouble with having a pile of parts on a piece of foam is protection - there's nothing stopping your components being damaged. That's why if you wanna try things like that, get one of those snazzy frames that shop techs use on test benches. But again, no good long term, the machine can't really be moved easily as parts - imagine turning up to a LAN and having to assemble it on the spot, then what would happen if someone trips on a lead and sends the motherboard hurtling to the ground...
It's all a compromise but it's one that ends up working well with some clever implementation.