Pump Performance Testing

The pump used in the CORSAIR Hydro XD3 is a Xylem DDC, which means it already has a history of reliable and good performance backing it. But as with every product we receive, it was put through the full test suite. Given this is a PWM pump, the first thing to test is its RPM response, and to do so, I used the pump in a simple loop of reservoir-in to reservoir-out, with pump power from an EVGA SuperNova 1300G2 PSU and PWM control from an Aquacomputer Aquaero 6 XT, which also provided RPM monitoring.


The Xylem DDC has always been like this, with a slow response of RPM to the PWM duty cycle at the higher end and a more linear drop until it gets to ~20% PWM duty cycle. We see the same here with the CORSAIR XD3 pump, which is rated for 4800 RPM (+/- 20%), and my sample hit 4711 RPM at 100% duty cycle, went down to only 4545 RPM at 60%, and then dropped linearly to 1299 RPM at 20% before staying there all the way down to 1% duty cycle.

In order to see how the pump performs, I used it in the same loop as before, but with a Dwyer 490-1 wet-wet manometer to measure pump head in PSI and a King rotameter to measure average flow rate in gallons per minute (GPM). This P-Q curve for a pump provides extremely useful information as it shows the average flow rate in a loop when any flow restriction is added from blocks and radiators, under others. To produce an ideal but realistic data set, the P-Q curves below are thus for the pumps in a closed loop with minimal flow restriction.


I have included other pumps that have been developed within the few last years, and we clearly see that the two Xylem pumps are generally better than the rest with only the Alphacool VPP755 in the same territory. The DDC in the CORSAIR Hydro XD3 has a higher maximum head pressure to help deal with higher restriction components, but has a lower maximum flow rate. The rest of the lot are hovering around the lower end with only the XSPC X2O 420 in the XSPC Ion and the Topsflo TDC doing better.