Quote Originally Posted by Fir3^StorM View Post
That curve? It's very close to be linear actually
Btw, martin used DDC3.2+XSPC top in the GTZ-FuZion testing, didn't he? the flow rate decline with a D5 should be even bigger.
Wow, you're right, I was wrong. It is almost linear.

However, I'm still sure you cannot do the calculation the way you did. If you fire up up Martin's estimater, plug in the Fuzion v2 and MCP 655 you will have a flow rate of 2.01 GPM. Fuzion -> Supreme yields 1.22 GPM or 0.79 GPM less.

Adding a D-Tek GFX to the loop and doing the same yields a difference of only 0.34 GPM. (1.34 GPM to 1.00 GPM)

If you take into account that pressure drop in the blocks is a function of flow rate, the results make sense even if the pumps PQ-curve is linear. But I guess I could be wrong again.

Anyway, if you added enough blocks to get the flowrate to less than 0.4 GPM and then replaced a GTZ with a Fuzion you would, by your example, have negative flowrate, which obviously makes no sense.