The top-end card from AMD is the HD 6990, a dual-GPU beast that can power through anything you throw at it. Now, thanks to the folks at PowerColor, it is getting even better with the addition of a full-cover waterblock. The PowerColor LCS HD6990 features a full-cover waterblock from EKwaterblocks to bring high-performance liquid cooling to the AMD HD 6990. The waterblock cools the card up to 30% better under full load than the air cooler. It features high-flow 3/8" and 1/2" fittings to better maximize the flow with captured o-rings to prevent leakage. You can use either fitting to better work with your setup. The LCD HD6990 features a dual BIOS switch to alternate between the stock and the overclocked setting, and when you flip it, you will get a core clock of 880MHz and a memory clock of 1250MHz. You will find four mini-DisplayPorts and one DVI port to connect any monitor you wish to the card.
The PowerColor LCS HD6990 should be available soon though no price was mentioned.