arterius2 the aquacomputer waterblock has parallel water flow thus less cooling performance compared to this one, which seems to have serial water flow.

Don't bet on it. The folks at aquacomputer didnt just did the parallel water flow just for the sake of it. They must have been test it to see wheter such design is warranted or not.And its not like they are in the bussines of making watercooling block since yesterday. I think a camparison would be in order.Even so, i would rather have 66 and 66 then 64 and 70 on the Gpu Temperatures.