[Alchemy]

This is quite a lot to comment on, so I thought I'd just take this one piece.

Originally posted by Gooserider
1. The CPU's need the most cooling, and one should not feed into the other, so they need to be in parrallel.

Not necessarily. This would be important if the water is heated up a few degrees by the first CPU, since the second CPU would be operating at a higher temperature. But generally the flow rate is such that heat input, even with multiple heat sources, is usually far less than a degree.

You might be better off putting them in parallel to reduce the pressure drop - two resistances in parallel create less pressure drop than two resistances in series - but the result of this is half the flow rate across each block, and typically worse cooling.

You'd have to try to be sure, but it's my opinion you'd get better results putting the CPU blocks in series.

2. To maximize the flow to the CPU's they should be plumbed w/ 1/2" tube, and my blocks (I'm going to make my own) should be designed to allow a high flow by staying fairly close to 1/2" worth of passage cross section while encouraging turbulence over the die area.

1/2" cross section seems decent. Again, it's only my opinion, but I was always a fan of the blocks with big internal volumes.

3. The drives and Northbridge don't make as much heat, so I can use smaller plumbing on them for lower flow.

If you're putting all these fans in the case I doubt you'd need to watercool the northbridge or HDD. Even a SCSI should be decent if it's in a position with plenty of airflow around it. If it's not . . . then yeah, WC the thing.

4. Resevoirs seem to be neutral or a good thing in regards to cooling, and make maintainance and operation easier...

Let's not forget their aesthetic appeal.

5. Optimal plumbing pattern is 'pump > rad > hot stuff > resevoir > pump'

Yeah, but again, the change in temperature of the water along the loop is very small, so what's most important is arranging things to prevent flow restriction. If putting the radiator right before the CPU block requires a 90 degree elbow, then you might be better off doing something else.

Good questions.

Alchemy