Thermaltake Big Water 760i Review @ 3DXtreme
 

At stock the Big Water 760i was impressive and completely overtook the stock cooler without a problem. I fear adding a GPU block with more heat would more than likely start to push this system further than it can really go. For $150 it's a great starter kit, a great alternative to air cooling and allow someone who might want to play with water cooling to enter the foray in a safe way.