Thanks Iandh,

I removed the ramsinks, applied more TIM and did not tighten the sinks down any more than snug. They are working well and I have the card clocked to 840/1200 easily. I glued a few copper sinks onto the hottest parts of your ramsinks to increase the surface area and they seem to get warm too. It's working great!

These things really cannot be tightened too much before you start to cause problems. Follow Iandh's advice, and not much more than finger tight is enough.