Optimization issues in Mirage league

I encountered optimization issues that frequently resulted in game crashes, black screens, and long texture reloads (time depends on the version of GPU drivers). The GPU temperature also increased significantly both in Mirage instance and near Varashta, reaching up to 80°, compared to 70° in other demanding games like DOOM. There are no problems with cooling system of my PC, airflow, fans and etc works perfectly.

Specs:
CPU: i5-12400F
GPU: Sapphire Pure 7700XT
RAM: 32GB DDR4
AMD driver version: tried 26.2.1, 26.3.1 and 25.12.1