Fellow PC builders, here's a fun one for you.

I took some "old" and no-longer-used PC parts and built my sister-in-law a gaming PC for her and her stepdaughter to use. It was a Christmas gift so the stepdaughter could play the Sims.

She has called me three times to tell me it's completely frozen - like hard locked, dead freeze, screen is displaying the last frame it was on but you can't interact with the PC in any way until you reset it with the power button.

She let it sit for an hour before she gave up. Two times this happened while stepdaughter was playing the Sims 4 and once it happened while my brother-in-law was watching YouTube videos.

Obviously, I went through the usual things you'd think in this situation and I had her bring the PC over so I could do some digging. Fully expecting to find a hardware issue, I tried the following:

1. I ran the Sims while also watching multiple YouTube videos in the background. Couldn't replicate the issue after about two hours.

2. I obviously checked the temperatures while gaming and YouTubing, checked the usual performance metrics and everything was great.

3. Ran OTTC stress tests - all of them. Under heavy loads, this thing was doing fine. Even at 100% utilization, the memory, graphics card, and cpu were fine. Did a power test too, fine. Did a "combined" stress test and all was fine.

4. Ran mem86, no issues with the memory, no bad sectors or errors.

5. Played Skyrim on ultra for several hours. This was a really fun way to troubleshoot.

6. Checked the event log from the day she had freezes. I can see where the event happened because leading up to the unexpected "power off" event, there were a ton of events related to various processes timing out. Seems like it was unable to connect with services and run certain background processes while it was frozen? I didn't see anything that really stood out to me as being a possible cause except...

7. in the event viewer, there were a few events related to Microsoft family safety. I set this up at the request of SIL so stepdaughter wouldn't get into anything she shouldn't. In the Event Viewer, it seems like maybe it wasn't verifying something correctly or didn't have permissions it needed? Upon Googling, I found some other folks with this error but I couldn't find anything about whether it caused freezing or not. Seems like one of the many events that just gives a warning but doesn't have any effect. One guy who had this issue had his computer freeze but disabling the family safety entirely did nothing. People in the comments thought it probably wasn't related. I also found another event that Google wasn't very helpful with. Might have been related to sound card but my sound card drivers are up to date and again, I have not been able to replicate the issue even when gaming and watching videos, so I don't know if it's related.

8. I ran the Windows System Files Checker and found no issues related to my Windows install.

I can't figure out why this would be happening only at her house. She says it froze after one hour of use every time. This brings me to the title of this post. My SIL moved into a really old house with sketchy wiring. My FIL told her the wiring is so bad that she needs to get it fixed immediately or risk a fire, so she's working on that. This house has a butler stairway, asbestos, and plaster/lathe walls if that tells you what we're dealing with here. This is the ONLY thing I can think of that would possibly be different between the two setups and maybe explain the freezing, but it just seems so unlikely to me that this is the cause.

Help?