Thanks for the reply.
The problem is that the 2gb has this plastic back piece that pops out of the card like a heat sync/protector? so that portion is touching my 1gb which is why i swapped the position.
Both cards are fat and take 2 slot positions and thats why they are very close to each other.
Do you tihnk water cooling would make a difference?
If you already have water cooling setup, or you planned to set it up, then ya, that's a good option for you. Water cooling takes away the problem of needing air flow between the cards, because the cooling takes place at the radiator's location not at the card's location.
However, if you don't already have water cooling, it would be about as expensive as it would be to just go out and get a 6970 or 570 which would also solve your issue and have similar performance with much less hassle.