Many people out there who are keen on getting one of AMDs R600 cards already have a watercooling setup I guess. Other people who plan to purchase such a card might plan on going the watercooling road as well and for these people the following note is highly interesting. The metal shim around the HD 2900XT cards is taller than the core, not flush nor is the opposite the case. Take a close look at the pictures below, some of you might have thought the core is raised higher than the shim by mistake. To proof the stated fact following a quote of Shamino from VR-Zone:

too bad the shim around the GPU is taller than the core

If you plan to use a water cooler in order to cool the card, which makes sense according to the preliminary thoughts regarding power consumption, you should double check if your cooler fits onto the card. It has to be either very narrow or needs a recess to be milled on it following the outer edge to some degree. Shown on the last picture is the DangerDen MAZE5 GPU block which served such recess in order to be compatible to the first X800 cards. The last solution would be to remove the shim, which will void the warranty of course.