Poor Man’s Flatness Test

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Simple and effective – Michael Yu

After recently discovering that I had poorly mounted my waterblock resulting in higher temperatures than should have been expected, I posted on some forums and got a very useful tip back.

From an end user point of view when buying a heatsink or waterblock, the only guarantee of flatness is that of the manufacturer’s. So how can an end user decide whether they have a bad mount because of themselves or the flatness of the waterblock or heatsink is to blame?

Here is the poor man’s flatness test:

An Overclocker’s Forum member (Marci) linked this pdf file and the Forum thread the tip came from is HERE.
Originally posted by Cathar as an exercise to show Reflective-ness =/= Flatness, images have been taken from the Froum thread.

First, print out the linked pdf file; get your waterblock or heatsink and hold the base to the printout so it is at a reasonably sharp angle – for example, 45 degrees. The base should start acting like a mirror, reflecting the grid you have printed out.

The results:




Not Flat

The more distorted the grid’s reflection, the more uneven the surface – a simple test but very telling.

Michael Yu


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