Don't know why it took me this long, but Cathar putting a number on it made me realize something:

The correct mounting pressure is dependant on the Thermal Interface Material.

In other words, The AMD spec isn't just for the AMD core, but for the AMD thermal pad included with the retail Heat Sinks. Same for Intel.

For example, look at this graph:

http://www.egc-ent.com/egc-ent/image..._graph_big.gif
(Image source from Googling)

Note that this is a graph of Thermal Conductance vs Pressure, the prior graph was of Thermal Resistance.

Notice the 2 best compounds at the top right of the graph. The Light blue compound is starting to level off as pressure increases, but the Dark blue compound below it is still improving rapidly with more pressure.

I would suspect that most TIMs marketed for use on CPUs would be designed to work with standard CPU clips, but for anyone trying more exotic TIMs, this might be an important point to consider.

Perhaps, also of interest for WB testing...

At the following Test and Research equipment manufacturer web site http://www.longwin.com/, and among the various CPU testing devices they produce, found a testing device named "LW-9052 Press Load Apparatus":

Edit: darn!! how can you insert and image on this thing?
http://www.longwin.com/IMAGES/9052%20(1).jpg
Oh well
Here is a link: http://www.longwin.com/PRODUCTS/9052.HTM

Having read on this forum references as to the:

A) numerous re-mountings of the water block necessary to get a "best fit"

B) The required flatness and evenness of both surfaces (CPU core and WB)

C) The importance that pressure variations (below 100PSI aka Point of Diminishing Returns) can have

Ask myself if it such a device would greatly increase the accuracy of test results, when benchmarking water blocks?

Not sure why the image tags are not working?

Yes that is a nice machine, cost more than my truck and all my computers combined though I would bet (which is only about $5,000). I doubt it would "greatly" increase the accuracy as most any serious tester remounts 5+ times. Would cut time way down though if you only had to mount and test a block once....

On the other hand.. having taken a "good look" at this device, constructing a DIY ghetto versión does seems to be a good possibility.

Edit: added following..

Question: Also, although I have never been involed in testing WBs, do you get different results every time you re-mount + test a WB? or does it comes to a point where various re-mounts + tests do offer same or very similar results?

If question 1 holds true, then will benefit by using such a device, simply because it will standarize the re-mounting + test process IMHO

Yes remounting generally will get different results but usually by a C or less. I usually can't pick up the difference with my half assed equipment.

Here is a graph from Bill Adams testing. He mounts them 10 times.

http://www.overclockers.com/articles720/S5cwdist.gif

http://www.overclockers.com/articles720/index02.asp

Within the max 0.231, and the min 0.225, assuming an 80 Watt source, the temps could differ by 1/2 degree.

Bill has also refined his application method: your results will vary ;)

He uses a 70watt source.

A little more info for the ones that are alergic to links. :D