I sympathize. I had a few WHEA error 18s last month. I ended up reinstalling Win 11 with a fresh installation (keeping no files), replacing my thermal paste on my CPU, reseating every stick of RAM and the CPU, and went with a lower RAM overclock. (I did more maintenance than this too, but the system was already uber stable before I did those.) Now, the system has been great for a couple of weeks without needing to replace any hardware. Here are my thoughts:
PSU - PSUs tend to be blamed a lot for things but are usually pretty durable. The only way I know of to test one though uses specialist equipment, so unless you have that, you'll have to try out the other suspect pieces first, and if that's all that's left after everything else checks out, replace it.
MB - If you see burned things on the MB, replace it. Otherwise, I suspect that it's fine. If anyone else has better tests that don't require specialist equipment, please add. lol
RAM - Did you increase the RAM's voltage and try playing? Did you leave only one DIMM of RAM in the MB when testing it? If not, you can try to run the memtest on each stick separately. You can also try to run EVE with only one DIMM at a time to see if the game crashes.
CPU - You set the MB to defaults, and that's good, but did you also remove the CPU cooler and replace the thermal paste? Did you clean out the CPU cooler of dust? How about overvolting while leaving other parameters the same? Or, how about increasing the Load Line Calibration values to reduce the chance of voltage drop making your system crash? You can try removing the CPU and reseating it too.
GPU - Have you tried running with a higher voltage with all other parameters at stock? Have you tried to downclock? Have you run any stress test benchmarks? Have you tried to replace the thermal paste? How about cleaning out the dust?
Good luck!
