Intel Skylake is throttling using regular cooling methods and requires delidding plus replacing the thermal interface material to be cooled effectively. The need for this procedure has been displayed by Splave at launch day and other overclockers in the following days. Roman from Overclocking.guide prepared a video to guide you through the process of thermal interface swapping.
In the video uploaded to the der8auer channel, Roman explains the process in detail. First, you remove the IHS (heatspreader) by cutting the silicon paste between the IHS and the CPU. Then, after cleaning the CPU and IHS, you add a new thermal paste on the CPU core. To make the CPU look like brand-new, you use silicon paste to re-attach the IHS to the CPU. After this procedure, your CPU may run up to 20°C cooler than before.
Check out the video by clicking on the image, or by clicking here. Good luck!