Quote Originally Posted by gmat
For the only reason that the motherboard full cover block is so restrictive, it kills the flow even with dual pumps. So i have dual pumps on the CPU+GPU loop, and a single pump on the motherboard loop.
and

Quote Originally Posted by Naekuh
yeah i wish people understood this..
the bridge on the nb -> Sb only allows so much without making it bulky.
I have found on both my systems, that flow is not important - there is less than 1.0 deg C differnce, keeping all else constant, running the pumps at full tilt, vs 8.5 - 9.0 Vdc via the bigNG or TMS-200. This have the pumps very quiet, pretty low flow, but still doing a great job.

Let's look at this analogy -> take a standard air-cooled system, let it idle, and disconnect the fan. Keep your hand on the HS, and feel how quickly that warms up. Now, with a fan-controller, adjust the fan to be barely rotating, and see how quickly that wisks heat away - within seconds, the heatsink is cool to the touch.

With watercooling, this is even more efficient for low flow conditions, due to water's efficiency. Yes, super-high flow will hel a little, and high-flow mght be needed where you have blocks, like the Swiftech Storm of days gone by, that needed pressure to try and atomize the water.

In our modern systems, again, for the last 1-2% performance, that extra flow might help a little, but for else, not an issue. I have a 480 Feser on the Wife's rig, a single disconnected the one D5, then, Ek full-cover for the eVGA 4-way SLI board, EK on the 5990, and Swiftie GTZ on the CPU - pretty restrictive from the EK full-cover block, overclocked to past 4Ghz, and pump at low flow, fans low speed, and a very happy system.

But let me stop these long replies, I am sure they're tiresome to read, apologies for that.

Enjoy, gotta start rewiring the AX1200 with spaghetti noodles HP Blackbird is waiting.