Managed to stabilize the CNB at 2.8G, however the CNB frequency does not seem to help in CB past 2.6G.

This is on cool water, however the old issue remains: I never remember to purchase proper hoses.
I am currently using silicone hoses with 8mm ID and they are super restrictive when combined with this waterblock.
The flow is less than 2 litres per minute.

The idle temperatures are great, however the flow is not enough to keep the block cool under the load.
Hotspot temperature is only 7?c lower than on air. Still it almost completes CB at 5.4G / 1.57V.