It will not just screw in and work. But you can get a mount for a cpu liquid cooler to go onto a gpu. What is your gpu? Here is a link to the cooler. http://store.nzxt.com/Kraken-G10-GPU-Bracket-Black-p/rl-krg10-b1.htm
So are you saying that using the H55 will work if I use the Kraken G10?