Well after a couple of months with hardware problems I finally realized that a dust filter on my Silverstone SST ST1000 PTS was completely filled with dust and was causing overheating while playing a sertan game.
LOL Been there. Still, I will never have a case again that does not have removable, washable dust filters.
It would be nice with a temp censor on the PSU that one could see in e.g. Hardware Info
Nice but, I don't see it happening. How would that temperature value get to any sort of monitor?
Where inside PSU will the sensor go? What type sensor? There is only 1 unused (besides several "common") pin socket on the 24-pin connector. All the PSU makers would have to agree to use that one, or another cable or an entirely new cable. Then all the motherboard makers would have to agree to use a corresponding pin on the motherboard. All the chipset/BIOS makers would have to agree on how and where to distribute that value so the various hardware monitors could use it.
It is near impossible to get that many hardware and software makers to agree on the time of day, let alone a "new" feature.
That said, I would suspect it was not your PSU overheating and but the CPU, GPU, RAM, or a motherboard component. This would be especially true if your PSU is bottom mounted over its own intake vent. I note that is a semi-fanless operation PSU meaning the fan stays off when cool and ramps up to full speed as temps rise. Even with a quiet case, since PSUs are mounted next to an outer case surface, I know I sure would hear the fan noise.
Either way, I use and recommend
Core Temp to monitor CPU temps in real time. Under Options > Settings > Notification Area, I have mine set to display "Highest temperature" only to avoid cluttering up the System Tray area. Then when I see my temps starting to hit and sit above higher than normal temps, that is my cue to clean my filters.