I'm pulling my hair out over an issue that has recently appeared out of nowhere. When my PC goes to sleep for more than a couple of minutes, it will not wake up again. On moving the mouse etc the fans spin very briefly but then it shuts down. Sometimes it will restart normally when I press the start or restart button, but frequently that doesn't work (nothing happens) and the only way to get it to start is by unplugging the PSU for a few seconds and then reconnecting it. Everything runs normally when it's awake. I haven't made any hardware changes recently and only software changes was Windows update to 23H2, but that may be a coincidence as I tried reverting to 22H2 and the problem persists. I have tried updating BIOS to 1905 (from 1807) but that didn't help. I was running happily for several months on EXPO II but tried clearing CMOS and reverting to basic memory settings and that didn't work. I even tried a fresh Windows install with minimal apps installed, and that didn't help. My system is X670E Hero, Ryzen 7 7800X3D, G-Skill 32GB 6000MHz kit (which is on the QVL), RTX 4090 and Corsair 1000W PSU. I'd really appreciate any suggestions.
