You should be running a power supply that can deliver at least 700 watts if you're looking into the RX 7700XT. You could use your current PSU, but spikes in power draw may cause unnecessary performance and crashes. If you don't want to upgrade your power supply, you can get the RX 6700XT instead, as it fits within your power constraints and performs better than the RX 7600. Hope this helped, take care.