I will mention Pump as Well.
I agree that first thing would be to clean rads and fans from dust
Then Open up the blocks if Rad cleaning not helps
Then Flush the rads maybe
I had the situation when culprit in similar situation was dying pump. It ended up with so low RPM that was barely moving the water around and my CPU temps were going Up to 75c. However your situation looks more that Pump works properly, otherwise CPU temp itself would hit the roof not only water temps would be high.
Where is your Water temp measuring diode? I use 4 Inlline diodes that i can see water temp in any place in my loop. After CPU Block , After VGA and after each RAD just before it goes back to CPU block.
I agree that first thing would be to clean rads and fans from dust
Then Open up the blocks if Rad cleaning not helps
Then Flush the rads maybe
I had the situation when culprit in similar situation was dying pump. It ended up with so low RPM that was barely moving the water around and my CPU temps were going Up to 75c. However your situation looks more that Pump works properly, otherwise CPU temp itself would hit the roof not only water temps would be high.
Where is your Water temp measuring diode? I use 4 Inlline diodes that i can see water temp in any place in my loop. After CPU Block , After VGA and after each RAD just before it goes back to CPU block.