Often times, if Windows freezes, it also won't record much of use in the event logs, but you can surely check, maybe you can spot something.
If not, you would just do some good old methodical troubleshooting to find the culprit. First, the stuff you can do in Windows, for example, read out the SMART data of the SSD with
CrystalDiskInfo. In the program's menu under "Function" -> Advanced Feature -> Raw Values, select "10 [DEC]" to have human-readable values, and you can press CTRL-S to save a screenshot.
Let us also check all the sensor data during a Cinebench run, using
HWinfo64. Open "Sensors", then expand all sensors by clicking on the little <--> arrows on the bottom, also expand the columns of the sensors a bit so everything can be read. Make it three big columns of sensors (or four, if the screen resolution is high enough). In the end, it should be a screenshot with all the sensors visible at once, like this:
Make sure the power plan in Windows is on "Balanced". Do nothing on the PC for a while (couple minutes), so the "minimum" baselines for the values are established. After that time in idle, then produce full CPU load with
Cinebench, and after completing a 10 minute run, when the CPU temperatures have stabilized at the highest level, take a screenshot of the sensor window and tell me the Cinebench score. On this screenshot, we can see how it runs in idle, as well as with fully multithreaded CPU load, the highest normal load you can encounter in daily use without resorting to an artificial stress testing tool like Prime95.
With that squared away, if it doesn't give any indication of a problem, then - since you're saying it happens more and more frequently lately - i would start by testing with a different PSU. Why? Because in PSUs they use a lot of so-called electrolytic capacitors, which are known to deteriorate with age (and this is accelerated with higher temperatures, such as inside a PSU in a cramped PC). So with increasing instability/problems, we should try to rule out the PSU first. Try to borrow a different PSU, but it has to be known good, not too old, and of
decent quality. Then you can connect it on-the-fly using its own cables (just put it next to the PC and hook up the cables instead of the original PSU's cables).
As you can see in
this video, the small form factor of such a system has some downsides when it comes to working on the system for troubleshooting or upgrading. Although i've seen worse from MSI, this one is actually still somewhat accessible. Anyway, if you find that the problems disappear with a suitable PSU for testing, then you're done, you need to get a new PSU. Maybe take a photo of your old one and we see if there's a good replacement available. If the problems don't go away with a different PSU, you'd continue, trying to rule out more things.
