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Since87 · 12-17-2002, 08:32 PM

First of all, I assume you are talking about parallel pelts with Maze2-2 type watercooling. Stacked pelts used this way definitely won't work.

If you want to have an idea what goes into calculating this stuff, have a look at this thread over at overclockers.com. Be warned, it's a lot to wade through.

To sum up, there are a lot of unknowns that I can only make guesses at without doing a lot of testing and calculations with specific hardware. A lot of the unknowns are related to the C/W of the hot side cooling system and the C/W of the cold plate.

The cooling through the coldplate is going to be less efficient with dual 172's because of the increased distance the heat must travel from the CPU to the pelt.

The cooling provided by the Maze2-2 waterblock is going to be more efficient because of the larger surface area to be cooled in a dual 172 setup. (Of course if you are going single 226, a Maze3-1 will likely give better hot side cooling than a Maze2-2.)

The most important issue that affects the comparison of dual 172's at 12V vs a single 226 at 12V is that, the dual 172 watt pelt will consume about half the power of the single 226 and the dual 172's will have somewhat more cooling capacity (Q) but lower dT. The lower heatload on the watercooling system probably cancels out the loss of dT of the dual 172's at 12V for the majority of watercooling systems.

My best educated guess, (With a lot of help from the Kryotherm calculator and a spreadsheet I wrote.) is that the dual 172's at 12V will get the CPU about 2C colder than a 226 at 12V. If you run your system 24/7, the money saved on power will pay for the second 172 in much less than a year.

Also, if you decide you want more cooling, you can connect a 5V supply in series with your 12V supply, to power the dual 172's at 17V. Increasing the voltage of a 226 above 12V will increase the CPU temperature with most water cooling systems.

12-17-2002, 08:32 PM	#8
Since87 Pro/Guru - Uber Mod Join Date: Sep 2002 Location: Indiana Posts: 834	First of all, I assume you are talking about parallel pelts with Maze2-2 type watercooling. Stacked pelts used this way definitely won't work. If you want to have an idea what goes into calculating this stuff, have a look at this thread over at overclockers.com. Be warned, it's a lot to wade through. To sum up, there are a lot of unknowns that I can only make guesses at without doing a lot of testing and calculations with specific hardware. A lot of the unknowns are related to the C/W of the hot side cooling system and the C/W of the cold plate. The cooling through the coldplate is going to be less efficient with dual 172's because of the increased distance the heat must travel from the CPU to the pelt. The cooling provided by the Maze2-2 waterblock is going to be more efficient because of the larger surface area to be cooled in a dual 172 setup. (Of course if you are going single 226, a Maze3-1 will likely give better hot side cooling than a Maze2-2.) The most important issue that affects the comparison of dual 172's at 12V vs a single 226 at 12V is that, the dual 172 watt pelt will consume about half the power of the single 226 and the dual 172's will have somewhat more cooling capacity (Q) but lower dT. The lower heatload on the watercooling system probably cancels out the loss of dT of the dual 172's at 12V for the majority of watercooling systems. My best educated guess, (With a lot of help from the Kryotherm calculator and a spreadsheet I wrote.) is that the dual 172's at 12V will get the CPU about 2C colder than a 226 at 12V. If you run your system 24/7, the money saved on power will pay for the second 172 in much less than a year. Also, if you decide you want more cooling, you can connect a 5V supply in series with your 12V supply, to power the dual 172's at 17V. Increasing the voltage of a 226 above 12V will increase the CPU temperature with most water cooling systems.