Best 69xx design for getting rid of heat?

[dlasher]

I'm trying to find a card design in the 69xx series that actually vents the heat out the back instead of pushing it around in the case. I've now tried 4 different 6950's, and none of them seem to vent the heat out the back. I'm tempted to try a 6970 or two.

Why do I care? 3-4 per board while keeping temps under 80C is very very hard unless the card is properly getting rid of the heat.

Suggestions?

 

[Ryu.Hayabusa]

The reference ATI card had a fan in the back that pushed air out to the back of the case.  The current designs by XFX, PowerColor, VisionTek, Sapphire, and I think I'm forgetting a manufacturer will usually place the fan in the middle for some odd reason (I guess to increase cool airflow to the core?).  I'm sure it works in 1-2 card configurations, but as you have said (and I've seen this myself), when stacked the airflow is crap.

I believe the 6970 still has the fan in the back on most manufacturers, though be sure to get detailed pictures of the actual item to confirm.  I'd recommend Sapphire if available, and stay as far away from XFX as possible.

There is always water cooling if you can't find a suitable card, though this will add ~$300-400.