Question H100i V2 not cooling properly? i5 9600k goes to 70-80C

[Mmelara851]

I bought an H100i V2 a long while ago and at first it was great with my old system. Max temps on it was 60C for the first three months. After this it would start going up 10C each month. I'd have to re-seat the cooler sometimes and would get only moderate success. I eventually upgraded my PC with the specs shown below and now still have temp issues. The CPU will reach 70-90C while gaming WITH turbo boost disabled. Does anyone else have this problem with the h100i v2? and should I just buy a new cooler? I have tried washers and it was no success.
Specs:
i5 9600K
H100i V2
MSI RTX 2070 Gaming Z
Asus Z370-A II Motherboard
500GB SSD
2TB + 320GB HDD
Corsair RM750x PSU

 

[Darkbreeze]

How long have you had this cooler in service?

 

[Mtop]

Get a new cooler pump may be going/gone bad, do fans spin up under load?