Had my Motherboard replaced now the fans loud

I have a alienware aurora and i was updating the bios and it got screwed up so they installed a new motherboard. The tech who came out had to take the Liquid cooling sink of the CPU and when he took the old stuff off he put all the grease in one spot put the sink back on and the fan and went on his way. The fan now wont stay outta 3000k in idle and dell says they have to send me a new heat sink because the core is getting to hot. What could be the problem? when the tech was putting the plugs back in he seemed confused and theres 3 different plug ins for fans. Theres the system fan, the CPU fan and then a memory fan and a different plug in named the liquid CPU. not all of these are plugged in and the CPU fan is missing maybe because the liquid cooling core but the system fan is so loud i cant stand sitting on the computer. any advice other then not buying from a manufacturer