DHL delivered the new pump very quickly from Swe so I drained, replaced pump with new one and took out gpu to attach cables correctly. Took about 3 hours so I am getting quicker.
Pump is much improved and no electronic squeal from it. It drained the small reservoir so much quicker so the flow rate on the 4.2 looks to be much greater than the 3.1. Can do office work with pump turned off so just fan noise and even at 100% it is not too bad.
There is still a capacitor hum but it is very light, I must be very sensitive to that frequency of sound. Could not get the Phanteks gpu block to light up, the cable looks to be plugged in correctly but doesnt seem to work. Something else to look into. The Corsair cpu block is low quality plastic but I really like how it casts light down onto the mobo.