Is your MOBO controlling or throttling the voltage to the pump? Make sure you are NOT using Q-Fan and that the pump is getting a full 12v.
Also, where/how are you measuring these idle temps?
Hi XmsYellowbeard, thanks for your reply.
The cooling fan is connected to the CPU connector on the board and the pump is connected to any 3 pin fan connector as per instructions. No I am not using Q-Fan. The temps were measured with the RealTemp software. The PC is not overclocked yet, but I ran Prime for an hour and the temp on one core (40C) only went as high as 43C then back to 41C.