I have been using my Antec H2O 620 for about a year on my old Intel Q6600 processor without any problems. Today I received my new system, which is an Asrock Z77 Extreme6 motherboard and and Intel i5 3570k processor. Everything works flawlessly, except for one thing: The 620 doesn't start, neither the pump or the fan. I have tried to plug the pump power cord into two different cpu fan connectors as well as a normal chassis fan connector on the motherboard, but nothing happens. To test if it was a motherboard malfunction, I tried to plug my old stock CPU fan into the CPU fan 1 connector, and it worked flawlessly. I then tried to plug the fan from the 620 directly into the chassis connector, without going through the pump, and it started to spindle as soon as the power was turned on.
I am in doubt whether this is because I forgot to do something / did something wrong during installation, or if there is something wrong with the pump unit. I have checked that the screws are tightened sufficiently, and I have tried to reinstall the entire unit, to no result. The only error through the installation process I can think of, is that I have no spare thermal paste, so I just used what was left over from the old system - there is paste on both the new processor and the pump unit, but could the pump refuse to start if new thermal paste isn't applied?
I hope you can help me out