My friend has exactly same Issue. Both monitors go black, he can hear us in discord and talk to us, but the game sound is dead and monitors won't turn back on without restarting PC. We checked everything. Temps seem to be normal, GPU stress tests don't cause similar issue. Like
@k4iser.88 we also undervolted and underclocked rtx 3070 and lowered settings a bit. So far the issue has disappeared. Glad to find out that this is likely caused by the game and not hardware issue itself.