I tought I had a crack too
Water was dripping from the block on the vga
After some good looking i noticed it was that the iron O-ring wich come with the mobo was squeezing the tube and made room for the water to come out.
After throwing away all the O-ring and using tie-wraps no leakage anymore and happy benching
You guys might wanna take a look at that, because it looks like the block is cracked but in fact it might be water from the tube leaking over the block (round the top)