GPU Boost will not increase the clock rate of the GPU as its name might suggest. Instead, the Honor technology will dramatically improve the power efficiency of GPUs in its smartphones to improve battery life. The manufacturer is claiming that a mid-range smartphone with GPU Boost can outperform a flagship smartphone without GPU Boost while allowing for HDR and higher frame rates in games.
https://www.notebookcheck.net/Honor-GPU-Turbo-technology-promises-30-percent-power-savings-in-smartphones.308096.0.html