Quote Originally Posted by Martinm210 View Post
While having a target flow rate is somewhere to start, the more I've been playing with this CPU block setup where I get the full picture, the more complex I'm seeing this pump heat issue becoming.

For each CPU block tested I'm recording flow rates, but also water and air temperatures. What I'm noticing is that even with the same pump, the more restrictive blocks have a lower water temperature. Even with the TFC 480, I'm seeing around .1C hotter water with the more free flowing blocks.

So in the end you might have higher flow rates, but also hotter water temperatures. The question then becomes, which is better or worse or does the end resulting performance on your other blocks better or worse.

In the end I think there is probably some sort of "Optimal" flow rate to shoot for and it's going to be a function of pump heat dump.

It's all splitting hairs at this point to the point it really doesn't make a difference in the real world, but I'm not entirely sure running a system at 2GPM with a known pump would be better than say undervolting the pump to 1 or 1.5GPM. I'm not really sure what to shoot for at this point but I know the differences are very small above 1GPM.
So, which would make the best bet?
a. GTZ resulting in approx. 1.1GPM and 0.1c colder water temp
b. FuZion resulting in approx. 1.5GPM and 0.1c warmer water temp?
The FuZion seems like a safer candidate.. although they're both good choices and top performers.

Quote Originally Posted by alacheesu View Post
It's not as simple as that. The more restriction already in your loop, the less of an impact replacing the FuZion with the GTZ will have in terms of flow reduction. Look at the PQ-curve of the pump, it's not linear. If you could do what you did, adding enough blocks would make the water flow the other way.

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.