Just thought I'd give everyone an update on this project. I ended up revising my design a few times along the way.
Fortunately, I found a guy that had an end mill which enabled me to channel out a bigger water block. (see pictures).
I had some trouble sourcing the 80W pelts as the store closed down after I ordered them (fortunately they never charged me). So I picked up a 65W pelt, which was all I could get at the time. It's mounted up and after "warming up" I'm getting about a 3-4c drop in coolant temp.
It's running off the stock PC powersupply and draws about 50W of power. The hot side of the peltier just has a basic heatsink on it at the moment, and it gets upto about 58c.
So I'm looking for better heatsinks to make the peltier more efficient, I now see what your saying about a second water circuit to absorb the heat. I may eventually end up going this way, but I wanted to avoid getting too complex if possible.
I'll keep you updated on how things progress.
