Hi there!
I'm Jewel with Kingston Technical Support and wanted to offer some assistance. This might not be the issue but the system does require memory to be installed in a particular way for it to work in triple channel mode. For the three modules to work together the memory needs to be installed in the A1, B1, and C1 slots which are the orange ones according to the manual. Hope that helps!
Thank you for choosing Kingston as your upgrade partner!