Things that i personally suggest to keep in mind:
1. Make sure that you are not overheating the gpu. Do not overclock gpu core or video memory at all.
2. Make sure that you have properly cleaned the latest driver:
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3. Make sure that you are using a Power Supply Unit that is adequate and performs well, and that you have properly connected all of the required power cables to the gpu. Check the PSU rail voltages, especially the +12v rail which is heavily used by your gpu.