One cool thing about Afterburner is you can make up to 5 profiles to switch to. I usually make #3 the stock profile and use #1 and 2 for undervolting/underclocking, then #4 and 5 for overclocking. Switch, test, reset, test again.
Cooling with that older card. Would be a good idea to take it apart re-paste and maybe re-pad it. The paste is almost certainly played by now. Would breathe new life into it for sure. More often than not it's all that's wrong with them.
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