Hello every one. I will try not to make this lengthy, but to best describe my experiences it may become that way.

I wanted to post here, as this specific thread led to my decision to purchase the Primochill Typhoon III. I am not new to modding or OC’ing and have many years of builds under my belt, my first being a 333mghz machine in 96. But I am new to watercooling and wanted to do it right. So I did my research first, choosing the parts I purchased by listening to the people who use them and their experiences/comments. I saw many negative comments about the fittings that come with this unit and the o-rings and the recessed o-ring grooves. I saw people say they didn't get any better performance/temps using the dual loops. But I read what was in this thread and made the choice to go with this unit as it fulfilled five of my goals, to save space, to run dual loops, to have a dual bay reservoir, it looks nice from the front of the case, and so many people here are talking highly of it.

I found it easy to install in my NZXT Tempest case (though I needed some longer screws), and easy to mount the MCP655 pump. The fittings, though plastic and proprietary to this unit, didn't leak even though I could move the hose a little within the compression fitting by hand. I ran the loops outside on the floor on a dark towel for 24 hours before installing everything in the case. Everything went well during pre-testing, install, and for about a week of overclocking and testing.
After many attempts at OCing my MB/CPU, and many voltage tweaks for stability, I found a stable 3.66 with an 1833fsb. All was going great. I was happy with my OC, was finally stable in Prime95 for 20 minutes several times, the CPU temp never went above 63 at load during those 20 minutes, so I decided to go for the 24 hour torture test.

Now to the part that doesn't make me so happy.

At about an hour into the CPU torture test my CPU maxed out at 66C. After a couple of hours I noticed a small amount of fluid under my case. I shut down and went looking for the source of the leak. When I opened the fill port at the top of the system (not the fill ports on the Typhoon III) fluid came out quickly as it was under a little pressure. After taking everything apart I found that the Typhoon III had developed cracks at the lower fitting hole on the return side of the unit. By design you can only hand tighten the fittings that come with the unit, so it’s not an issue of over tightening a fitting. It was only after the water temps went up to 66 degrees Celsius and remained there for over two hours during the 100% CPU test did the leak develop. So I’m wondering if the small cracks were there when I purchased the unit and only after the cooling system heated up and pressurized did they start to leak. To test it outside the cooling loop I ran tubes from the inlet to the outlet ports to seal it, and filled it up with cold water to test it. It did not leak. I then put the unit on the back porch to heat up in the sun. After 15 minutes or so the leak was evident. So I cannot tell you if they were there before or not as it wasn’t until after about a week during a stress test of the system that the leak started. Or maybe it was an issue with pressure within the cooling system after the system ran for hours at 100% CPU load that caused the crack in the possible faulty manufactured unit.

I am in the process of hooking everything back up without the typhoon. I have to put my video loop on the same loop as my MB now and am curious what the affects will be of having 6 WB’s in the same loop, and without having a res at all.

I sent an email to Brain at primochill a few days ago but have yet to receive a response.