[Hoot]

That explains it. Thanks for taking the time to elaborate on that Stew. I eagerly await the second notice that the G5s are ready to ship! Meanwhile, I'm still wrestling with getting the darn blocks to sit perfectly flat on the die repeatedly. Harder than it sounds for some reason, but I'm resourceful. I'm going to look into the chance that the tapped ferrules connected to the backing plate, which the mounting screws go into may not be perpindicular to the backing plate tonight.

Regarding Bills testbed. I have great respect for it also. The only place I diverge from it is the fact that in using a copper extension of the copper body as a die simulator, versus the (assumed) silicate that typically is used in a CPU die, does not repersent the same source impedance of the heat energy. Examined as two separate worlds, they are great, but I personally am more interested in a testbed that simulates what I will encounter in real use, versus the ideal independent testbed. I do not look for a direct correlation between the two testbed results degree for degree, but more in the direction of trends.

As you know, we're about at the end of our rope with ambient cooling, until some major seachange occurs in the TIM barrier. I forget where I read it, but I saw a web site with a hybrid passive and active transport IHS, using imbedded, multi-dimensional path TEC technology. Sounded good, at least in concept. Another site talked about something I've pondered for some time. Using a slurry cooling solution with suspended microparticles of a substance that had 2-3 times the heat carrying capacity of water. That still would not help with the TIM barrier issue. Lastly, I wish I had the tools necessary to experiment with sintering copper or silver. I have some ideas about a baseplate with a sintered surface on the water side that is impermeable on the die side. Maybe it's already been tried...

I'm always looking for better hardware and if I could find a pump, either AC or DC, that ran as quiet as my 1250, but with significantly higher performance, I'd probably pick one up. Been watching the Iwakis on Ebay, but the Walchem/Iwaki site does not list sound pressure ratings for their pumps. That MD30rz-No7 looked tempting earlier today but I do not have enough knowledge about the sweet spot between wattage, noise level and raw capacity to make an informed investment yet.

Hoot