Well, I'm glad that someone picked up on my momentary lapse of reason, about power. I was thinking about it throughout the day, when I realized that what I wrote made no sense whatsoever.
But I don't think I'm very far off.
All in all, the lab condition should simulate, as closely (but reasonably) that of a PC. I think that we all agree there.
Using a high power resistor, and mounting it to some plate, the size of a CPU, is one way to achieve consistency in results, but it certainly is not a proposition that simulates a PC by recreating the power output of a CPU, and that power definitely cannot be simply calculated as I stated above (P=VI). (but I do believe that with the right power supply, the voltage spikes/drops would not be a factor).
Back to square one.
How do we simulate a CPU? How do we reproduce the power that a CPU generates? How do we measure that power? Should we consider max power, or average power? Should we test for max power +25% ? If all we're calculating is the heat transfer rate of a waterblock, is any of this relevant? What about water temp?
How do we deal with the other factors that dissipate power, beyond the waterblock (i.e. CPU to air, CPU to socket, ventilation, etc...)?
Can we do this cheaper than using a CPU and mobo? How does AMD do these tests?
And as unregistered pointed out (BillA?), there is even more info that we've mentionned (although, I will point out, I did refer to some of them, just not directly).
1-Total system heat capacity
as discussed here:
http://forums.overclockers.com.au/sh...threadid=60614
(Hello Aussies!)
This goes back to my point that some people believe that starting up a system, then noting data right away, or only after a few minutes, is acurate, when really, it's not. In short, heat accumulates in every single component, and is dissipated by each one of those components at different rates. (that's why I'm considering finned copper tubing).
2-Pressure drop across the waterblock: yes, it exists. yes it is a factor (and should be measured), but most importantly, it is a result of the flow rate used in the test. Knowing that info though, would help greatly in selecting a proper pump. I've always said that the waterblock is by far the biggest flow restrictor (unless the tubing is innapropriately sized, but I'm assuming otherwise).
Fixitt: you're right about the lengthy report not being fully read/understood, but the report doesn't have to have all that info in the main text, but should have references. The conclusion of the report should be able to satisfy just about anybody. As to why someone would take the time to write all that up, that's a personal issue.
PowerHouse is right, in that the objective of writing/testing anything is to be able to tell the average bloke which pieces he should get, and telling him what he needs to know. If PowerHouse (I'll use you as our "average bloke") doesn't understand the purpose of clamping, then he'll need to know, and how to do it.
The results to the tests could be posted in a table, in this form:
WATERBLOCKS
a)C/W
b) optimal gph
c) psi drop@that gph.
RADIATORS
a) heat dissipation rate (graph?)
b) optimal gph
c) psi drop at that gph
d) optimal air flow (graph?)
and so on. Knowing that info, any Joe, could mix and match, according to his budget. (The above is a proposition, is not complete, and is meant to spark the discussion about how to post results). Sorry PowerHouse, but telling you specifically which rig to get, could only bring on a number of liabilities: I'd rather give you the figures, and let you choose, that way, I'm not going to get sued!
PowerHouse: The purpose of water-cooling is not always for overclock. Some people just want to water cool to reduce the noise. If you are watercooling to overclock, then you would more than likely be using a thermo couple as well (otherwise, what's the point?).
If results posted are accurate to +/- 1 degree, then that may work, as long as the differences between the items tested are not within that range!