My Sapphire RX 7800 XT 16G keeps crashing with parity errors during heavy loads in GoW Ragnarok. What do I do?

This Polar Edition card felt like a gamble at 4K Ultra—I was getting random crashes every twenty minutes. The system logs were filled with GPU driver resets, making it clear that the core was unstable above 2.5 GHz. I tried enabling 'Performance Boost' in the BIOS, which was a disaster; crashes went from once an hour to once every ten minutes. I felt totally defeated. I eventually downclocked the core to 2.3 GHz, switched the core voltage from Auto to a manual 1.1V, and loosened the memory timings. After six hours of Prime95 stress testing, the system didn't throw a single error, and the crashes stopped. I lost about 4 FPS on average, but in real gameplay, you can't even tell the difference—stability is way more important than a few frames. GPU temps are now 62-68°C and VRAM is 75-81°C. I backed up the profile via the motherboard tool, but it's annoying that a factory OC card needs a downclock.