MorePowerTool will help you push the Radeon Rx 5500 XT to the max.
Overclock Your Radeon RX 5500 XT To 2.1 GHz On Air With This Tool : Read more
Overclock Your Radeon RX 5500 XT To 2.1 GHz On Air With This Tool : Read more
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I remember someone at AMD told a YouTuber (Steve from GN perhaps) that you would need to learn new tricks to overclock past default restrictions on the new NAVI cards. Doesn't seem so now that you can tune power taples, just like existing VEGA cards.