Very high CPU temperatures are usually the symptoms of malfunctioning liquid cooling loop, assuming the contact between CPU heat spreader and water block itself is good and that the water itself is adequately cooled within the radiator. This can occur either due to:
- Malfunctioning or non-working water pump: The symptoms usually include rapid spike in temperature when stressing your CPU to the maximum (for example with Prime95 software). Make sure the pump is plugged in to the power connector and that the liquid is indeed flowing in your system. You should feel the pump vibrating in your hand when operating and the water should be moving inside the reservoir. Observe the flow indicator or flow meter reading if present.
- Clogged micro channels in the water block: Micro channels can get clogged easily with various dirt particles and impurities, especially with plasticizer powder which has leached from the tubing. The symptoms usually include rapid spike in temperature when stressing your CPU to the maximum, flow rates are very low. Visually inspect the water block internals for any buildup or contamination and clean the system if necessary. In case the water block with translucent acrylic top is employed this inspection can be done without disassembling the system.
- Kink in the liquid cooling tubing: Very similar symptoms to both above described. Thin-walled tubing may collapse easily under low radius turns or when obstructed by other computer chassis elements such as closing side panel doors. Check the tubing for any signs of kink which restrict the flow.
Another culprit could be partially or completely defective CPU. Some CPU's runs at higher temperatures than the others. Overheating of the CPU can also occur due to:
Poor thermal contact within the CPU itself: Some CPUs, such as Intel LGA-1150 socket based Haswell and older, socket LGA-1155 based Ivy Bridge are notorious for their poor thermal contact between the CPU die and the heat spreader (IHS) itself due to the use of poor TIM. These CPUs are known to run very hot (80°C+) even on factory set frequencies. For best performance it is usually recommended to replace the TIM between the die and the IHS or to even run the processor de-lidded. Both require hazardous IHS removal which voids processor's warranty but can lead to temperature decrease of 30°C and higher.
Upon exhausting all suggestions feel free to contact EK Support.